U.S. patent application number 10/223700 was filed with the patent office on 2003-08-07 for image recording material.
This patent application is currently assigned to FUJI PHOTO FILM CO., LTD.. Invention is credited to Fujimaki, Kazuhiro, Sorori, Tadahiro.
Application Number | 20030146965 10/223700 |
Document ID | / |
Family ID | 19081581 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030146965 |
Kind Code |
A1 |
Fujimaki, Kazuhiro ; et
al. |
August 7, 2003 |
Image recording material
Abstract
A negative image recording material on which an image is
formable by exposure, comprising (A) a specific polymer compound
that has at least one carbon-carbon double bond in a side chain
thereof and a glass transition temperature of 80.degree. C. or
more, and is soluble in an aqueous alkaline solution, (B) a
light-heat converting agent, and (C) a compound that generates
radicals by exposure using light of a wavelength absorbable by the
light-heat converting agent. The negative image recording material
may also preferably includes (D) a radical-polymerizable compound.
Preferably, the (A) specific polymer compound contains at least 1.5
meq/g of the carbon-carbon double bond in the side chain
thereof.
Inventors: |
Fujimaki, Kazuhiro;
(Shizuoka-ken, JP) ; Sorori, Tadahiro;
(Shizuoka-ken, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 Pennsylvania Avenue, NW
Washington
DC
20037-3213
US
|
Assignee: |
FUJI PHOTO FILM CO., LTD.
|
Family ID: |
19081581 |
Appl. No.: |
10/223700 |
Filed: |
August 20, 2002 |
Current U.S.
Class: |
347/105 |
Current CPC
Class: |
B41C 2210/04 20130101;
B41C 1/1008 20130101; B41C 1/1016 20130101; B41C 2210/22 20130101;
B41C 2201/14 20130101; B41C 2210/24 20130101; Y10T 428/1405
20150115; B41C 2201/02 20130101; B41C 2210/266 20130101; B41C
2210/06 20130101 |
Class at
Publication: |
347/105 |
International
Class: |
B41J 002/01 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 23, 2001 |
JP |
2001-253217 |
Claims
What is claimed is:
1. A negative image recording material on which an image is
formable by exposure, comprising: (A) a specific polymer compound
that has at least one carbon-carbon double bond in a side chain
thereof and a glass transition temperature of 80.degree. C. or
more, and is soluble in an aqueous alkaline solution; (B) a
light-heat converting agent; and (C) a compound that generates
radicals by exposure using light of a wavelength absorbable by the
light-heat converting agent.
2. The negative image recording material according to claim 1,
further comprising (D) a radical-polymerizable compound.
3. The negative image recording material according to claim 1,
wherein the glass transition temperature of the (A) specific
polymer compound is 100.degree. C. or more.
4. The negative image recording material according to claim 1,
wherein the (A) specific polymer compound contains at least 1.5
meq/g of the carbon-carbon double bond in the side chain
thereof.
5. The negative image recording material according to claim 1,
wherein the (A) specific polymer compound has at least one amide
group in a side chain thereof.
6. The negative image recording material according to claim 1,
wherein the (A) specific polymer compound has at least one
constituent unit derived from a styrene derivative.
7. The negative image recording material according to claim 1,
wherein the principal chain structure of the (A) specific polymer
compound includes at least one selected from the group consisting
of poly(meth)acryl resin, polystyrene resin, polyurethane resin,
and acetal-denatured polyvinyl resin.
8. The negative image recording material according to claim 1,
wherein the (A) specific polymer compound includes, in a side chain
thereof, at least one of the groups represented by the general
formulae (1) to (3): 56wherein R.sup.1 to R.sup.11 independently
represent a monovalent organic group; X and Y independently
represent an oxygen atom, sulfur atom or --N(R.sup.12)--; and Z
represents an oxygen atom, sulfur atom, --N(R.sup.13)-- or
optionally substituted phenylene group.
9. The negative image recording material according to claim 6,
wherein the (A) specific polymer compound contains the constituent
unit derived from the styrene derivative at least 30 mol-% relative
to 100 mol-% of the total units in the polymer.
10. The negative image recording material according to claim 6,
wherein the side-chain structure represented by the general
formulae (1), (2) and (3) is linked to a constituent unit of a
styrene derivative constituting the (A) specific polymer
compound.
11. The negative image recording material according to claim 6,
wherein the constituent unit derived from the styrene derivative
constituting the (A) specific polymer compound has a structure
represented by the general formula (4): 57wherein R.sup.13
represents a hydrogen atom or a C.sub.1-5 alkyl group; and R.sup.14
to R.sup.18 independently represent a monovalent organic group.
12. The negative image recording material according to claim 6,
wherein the constituent unit derived from the styrene derivative
constituting the (A) specific polymer compound is represented by
the general formula (5): 58wherein R.sup.19 represents a hydrogen
atom or a C.sub.1-5 alkyl group, and R.sup.20 to R.sup.24
independently represent a monovalent organic group, with at least
one of R.sup.20 to R.sup.24 having a structure represented by the
general formula (1), (2) or (3).
13. The negative image recording material according to claim 1,
wherein the weight average molecular weight of the (A) specific
polymer compound is 6,000 or more.
14. The negative image recording material according to claim 1,
wherein the weight average molecular weight of the (A) specific
polymer compound is 50,000 to 200,000.
15. A negative image recording material on which an image is
formable by exposure, comprising: (A) a specific polymer compound
that has at least one carbon-carbon double bond in a side chain
thereof and a glass transition temperature of 80.degree. C. or
more, and is soluble in an aqueous alkaline solution; (B) a
light-heat converting agent; and (C) a compound that generates
radicals by exposure using light of a wavelength absorbable by the
light-heat converting agent, wherein a softening temperature of an
image recording layer formed by (A), (B) and (C) is 60.degree. C.
or more.
16. A planographic printing plate precursor that includes a
hydrophilic support and a photosensitive layer on the support,
wherein the photosensitive layer comprises: (A) a specific polymer
compound that has at least one carbon-carbon double bond in a side
chain thereof and a glass transition temperature of 80.degree. C.
or more, and is soluble in an aqueous alkaline solution; (B) a
light-heat converting agent; and (C) a compound that generates
radicals by exposure using light of a wavelength absorbable by the
light-heat converting agent, wherein the planographic printing
plate precursor is exposable to a light having a power density of
at least 5000 W/cm.sup.2.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a heat mode-compatible
negative image recording material on which an image is formable due
to heat mode exposure using an infrared laser, and in particular to
a negative image recording material that can form a planographic
printing plate that has excellent printing resistance and in which
the strength of an image portion is high.
[0003] 2. Description of the Related Art
[0004] The development of lasers in recent years has been
remarkable. In particular, high-output, compact solid-state lasers
and semiconductor lasers having an emission range in the near
infrared to infrared range (referred to as infrared lasers below)
are being developed. These infrared lasers are extremely useful as
an exposure light source at the time a printing plate is formed
directly on the basis of digital data from a computer or the
like.
[0005] Negative planographic printing plates exposable to an
infrared laser use, as a recording layer, a negative image
recording material that includes an infrared absorbent, a
polymerization initiator that generates radicals by light or heat,
and a polymerizable compound. Usually, the negative image recording
material utilizes a recording system where the radicals generated
by light or heat act as an initiator to trigger a polymerization
reaction of the polymerizable compound, whereby the recording layer
of the exposed region is cured to form an image portion.
[0006] Negative image forming materials have poor image formability
in comparison with positive image forming materials, in which
dissolution of the recording layer is caused by the energy from
infrared laser irradiation. For this reason, negative image forming
materials are generally heated prior to being developed in order to
promote curing reaction by polymerization to form a stronger image
portion.
[0007] As printing plates using a recording layer that utilize such
an image forming mechanism, printing plates are known that use, as
a recording layer (photosensitive layer), a photo- or
heat-polymerizable composition, as disclosed in Japanese Patent
Application Laid-Open (JP-A) Nos. 8-108621 and 9-34110. Although
these recording layers have excellent high sensitive image
formability, there are problems in that adhesion between the
recording layer and the substrate is low and printing resistance is
poor when a substrate that has been made hydrophilic is used as the
support.
[0008] The use of high-output infrared lasers for exposure is also
being studied in order to improve sensitivity, but there is a
problem in that the optical system may be polluted due to ablation
of the recording layer at the time of laser scanning.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide a
negative image recording material that can form a planographic
printing plate that has excellent printing resistance and storage
stability, in which the strength of an image portion is high, and
in which an unwanted curing reaction arising during ordinary
storage is suppressed.
[0010] As a result of extensive study, the present inventors found
that, by selecting a polymer compound having an unsaturated bond in
a side chain and a specific glass transition temperature as an
alkali-soluble polymer compound used in an image recording
material, excellent recording becomes possible in which the
strength of an image portion is high.
[0011] Namely, a negative image recording material of the invention
comprises: (A) a specific polymer compound that has at least one
carbon-carbon double bond in a side chain thereof and a glass
transition temperature of 80.degree. C. or more, and is soluble in
an aqueous alkaline solution; (B) a light-heat converting agent;
and (C) a compound that generates radicals by heat mode exposure
using light of a wavelength absorbable by the light-heat converting
agent.
[0012] The negative image recording material may further comprise
(D) a radical-polymerizable compound.
[0013] Although the mechanism resulting in the working of the
invention is not entirely clear, it is thought that an image having
excellent strength can be obtained because the glass transition
temperature of the compound itself is at least 80.degree. C., which
is a comparatively high temperature, as a result of using, as the
polymer compound soluble in an aqueous alkaline solution, a polymer
compound that has at least one carbon-carbon double bond in a side
chain thereof and a glass transition temperature of at least
80.degree. C. Usually, a chemical reaction occurs more easily and
excellent image formability is obtained with a fluidic material
(i.e., a material that is flexible), with respect to materials that
utilize a chemical reaction such as a polymerization reaction and a
crosslinking reaction to form an image as in the case of negative
image forming materials. However, the fact that the chemical
reaction occurs easily conversely results in a reduction in
stability. For instance, film remains at unexposed regions due to
an undesired chemical reaction arising even under ordinary indoor
and outdoor storage temperature conditions, and the non-image
portion becomes easily contaminated when the material is used as a
planographic printing plate. The polymer compound used in the
invention has a reactive double bond, but because its glass
transition temperature is high, the recording layer itself formed
from this material also has a high glass transition temperature. A
strong and rigid layer is formed that is not fluidic under ordinary
indoor and outdoor storage temperature conditions. Under such
conditions, the unexposed region has the characteristic of
excellent stability, and the exposed region is heated by heat mode
exposure to a temperature that is higher than the glass transition
temperature, whereby the recording layer is instantaneously melted
and becomes fluidic, a chemical reaction is triggered, curing is
effected rapidly, and an image is formed. By using the specific
alkali-soluble polymer compound of the invention in this manner, it
is possible to obtain an image recording material that has both
excellent storage stability and excellent image formability and,
when this recording material is applied to the recording layer of a
planographic printing plate, to obtain a printing plate that has
excellent printing resistance and excellent storage stability.
[0014] In the invention, "heat mode-compatible" means that
recording is possible by heat mode exposure. The definition of heat
mode exposure in the invention will now be described in detail
below. As described by Hans-Joachim Timpe in IS&Ts NIP 15:
International Conference on Digital Printing Technologies, Orlando,
Fla., (1999), p. 209, it is known that there are roughly two modes
of processes by which an image is formed through a chemical change
or a physical change resulting from light-excitation of a
light-absorbing substance (e.g., a dye) in a photosensitive
material. One mode is the so-called photon mode, in which the
optically excited light-absorbing substance is inactivated by a
photochemical interaction (e.g., energy transfer and electron
transfer) with another reactive substance in the photosensitive
material and the activated reactive substance triggers a chemical
or physical change necessary to form an image. The other mode is
the so-called heat mode, in which the optically excited
light-absorbing material generates heat and is inactivated a
reactive substance uses this heat to trigger a chemical or physical
change necessary to form an image. Besides these modes, there are
also special modes such as ablation, in which the substances are
explosively scattered due to local concentration of light energy,
and multiple photon absorption, in which a large number of photons
are absorbed at once. However, description of these modes will be
omitted here.
[0015] Exposure processes utilizing the respective modes described
above are called photon mode exposure and heat mode exposure. The
technical difference between photon mode exposure and heat mode
exposure is whether or not the energy amount of the numerous
photons to be exposed can be summed up and used with respect to the
energy amount of the intended reaction. For example, let us suppose
that "n" number of photons is utilized to initiate a certain
reaction. Because photochemical interaction is utilized in photon
mode exposure, the energy of plural photons cannot be added
together and used due to the law of conservation of quantum energy
and momentum. In order to cause some kind of reaction, it is
necessary to satisfy a relationship in which the energy of one
photon.gtoreq.energy of the reaction. In heat-mode exposure,
however, it becomes possible to sum up energy amount because heat
is generated after optical excitation and optical energy is used
after being converted to heat. Accordingly, a relationship in which
the energy amount of `n` photons.gtoreq.reaction energy amount is
sufficient. However, this energy amount summing is subject to
restriction by heat diffusion. That is, if the next light
excitation-inactivation process occurs and heat is generated before
the previously generated heat is lost by heat diffusion from the
exposed portion (reaction point), the heat almost invariably
accumulates and the temperature of that portion rises. However, if
the next generation of heat is delayed, the heat is lost and does
not accumulate. That is, in heat mode exposure, the results are
different between a case where light of a high energy amount is
irradiated for a short period of time and a case where light of a
low energy amount is irradiated for a long period of time, even if
the total exposure energy amount is the same in the two cases.
Irradiation over a short period of time is more effective for heat
accumulation.
[0016] Of course, although there are cases in which a similar
phenomenon occurs due to the influence of subsequently generated
diffusion, this basically does not occur in photon mode
exposure.
[0017] From the standpoint of the characteristics of the
photosensitive material, in the photon mode, the inherent
sensitivity (energy for the reaction necessary to form an image) of
the photosensitive material is constant with respect to the
exposure power density (w/cm.sup.2) (=energy density per unit
time). However, in the heat mode, the inherent sensitivity of the
photosensitive material increases with to the exposure power
density. Accordingly, if exposure time is fixed to the extent that
productivity that is actually practically necessary can be
maintained, it is ordinarily possible to increase sensitivity by
about 0.1 mJ/cm.sup.2 in the photon mode, but it becomes easy for
low exposure fogging to occur in the unexposed portion because a
reaction occurs regardless of how small the exposure amount is. In
heat mode exposure, however, a reaction does not occur unless the
exposure amount is higher than a certain level. Moreover, although
about 50 mJ/cm.sup.2 is ordinarily necessary in view of the
relationship with the thermal stability of the photosensitive
material, the problem of low exposure fogging can be avoided.
[0018] In heat mode exposure, it is necessary for the exposure
power density at the plate surface of the photosensitive material
to actually be at least 5000 W/cm.sup.2 and preferably at least
10000 W/cm.sup.2. However, although not stated in detail here, it
is not preferably to utilize a high-power density laser of at least
5.0.times.10.sup.5 W/cm.sup.2 because of problems such as ablation,
pollution of the light source, and the like.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The negative image recording material of the present
invention comprises (A) a specific polymer compound having at least
one carbon-carbon double bond in a side chain thereof, having a
glass transition temperature of 80.degree. C. or more, and being
soluble in an aqueous alkaline solution (also referred to
hereinafter as the specific alkali-soluble polymer); (B) a
light-heat converting agent; and (C) a compound forming radicals
(also referred to hereinafter as the radical initiator) by light
exposure by using light at a wavelength capable of being absorbed
by the light-heat converting agent, characterized in that the
negative image recording material is capable of forming an image by
light exposure.
[0020] Hereinafter, the compounds which can be contained in the
negative image recording material of the invention are
described.
[0021] (A) Specific Alkali-soluble Polymer
[0022] In the invention, the specific alkali-soluble polymer should
have a glass transition temperature of 80.degree. C. or more.
[0023] When the specific volume of a polymeric substance is
measured as a function of temperature, the "glass transition
temperature" (also referred to hereinafter as Tg) in the invention
refers to a temperature corresponding to an intersecting point of
the two straight lines, as defined in "Kobunshi Kagaku" (Polymer
Chemistry) (published in 1993 by Kyoritsu Shuppan Co., Ltd.), and
can be measured by a differential scanning calorimeter (DSC). The
Tg of each polymer compound in the invention is also Tg measured by
DSC.
[0024] The specific alkali-soluble polymer selected is the one
having a Tg of 80.degree. C. or more, more preferably 100.degree.
C. or more from the viewpoint of stability. The upper limit of the
Tg is not particularly limited, but from the viewpoint of
sensitivity and image formability, the Tg is preferably 250.degree.
C. or less.
[0025] The backbone structure of the alkali-soluble polymer having
a Tg of 80.degree. C. or more is not particularly limited because
the polymer can have the desired Tg by introducing bulky functional
groups such as alicyclic group and aromatic ring and cohesive
functional groups such as amide group into units constituting each
resin. As shown below, the backbone structure is preferably
poly(meth)acryl-based resin, polystyrene-based resin,
polyurethane-based resin and polyvinyl resin modified with acetal,
among which polystyrene-based resin is preferable for use in a
planographic printing plate in consideration of the influence
thereof on other printing performance such as adhesion.
[0026] The specific alkali-soluble polymer used in the invention
should have, in a side chain in the structure thereof, at least one
carbon-carbon double bond, and in a preferable embodiment, the
"carbon-carbon double bond" structure is a structure having, in a
side chain thereof, at least one of the groups represented by the
general formulae (1) to (3) below. This resin soluble in an aqueous
alkaline solution and used as a binder resin in the negative image
recording material has at least one "carbon-carbon double bond" in
a side chain thereof, and this resin may have, in a side chain
thereof, at least one of the groups represented by the general
formulae (1) to (3) whose structure contains a "carbon-carbon
double bond", and as a matter of course, the resin may have some or
all of these groups simultaneously.
[0027] Hereinafter, the side chains represented by the general
formulae (1) to (3) are described in detail. 1
[0028] In the general formulae (1) to (3), R.sup.1 to R.sup.11
independently represent a monovalent organic group; X and Y
independently represent an oxygen atom, sulfur atom or
--N(R.sup.12)--; and Z represents an oxygen atom, sulfur atom,
--N(R.sup.13)-- or optionally substituted phenylene group. 2
[0029] In the general formula (1) above, R.sup.1 to R.sup.3
independently represent a monovalent organic group, wherein R.sup.1
preferably represents a hydrogen atom or an optionally substituted
alkyl group among which a hydrogen atom or a methyl group is
preferable because of higher radical reactivity. R.sup.2 and
R.sup.3 independently represent a hydrogen atom, halogen atom,
amino group, carboxyl group, alkoxy carbonyl group, sulfo group,
nitro group, cyano group, optionally substituted alkyl group,
optionally substituted aryl group, optionally substituted alkoxy
group, optionally substituted aryloxy group, optionally substituted
alkyl amino group, optionally substituted aryl amino group,
optionally substituted alkyl sulfonyl group and optionally
substituted aryl sulfonyl group, among which a hydrogen atom,
carboxyl group, alkoxy carbonyl group, optionally substituted alkyl
group and optionally substituted aryl group are preferable because
of higher radical reactivity.
[0030] X represents an oxygen atom, sulfur atom or --N(R.sup.12)--
in which R.sup.12 represents a hydrogen atom or a monovalent
organic group, wherein R.sup.12 includes optionally substituted
alkyl groups, among which a hydrogen atom, methyl group, ethyl
group and isopropyl group are preferable because of higher radical
reactivity.
[0031] The substituent group which may be introduced into the
optionally substituted group includes an alkyl group, alkenyl
group, alkynyl group, aryl group, alkoxy group, aryloxy group,
halogen atom, amino group, alkyl amino group, aryl amino group,
carboxyl group, alkoxy carbonyl group, sulfo group, nitro group,
cyano group, amide group, alkyl sulfonyl group and aryl sulfonyl
group. 3
[0032] In the general formula (2), R.sup.4 to R.sup.8 independently
represent a monovalent organic group, and preferably R.sup.4 to
R.sup.8 represent a hydrogen atom, halogen atom, amino group,
dialkyl amino group, carboxyl group, alkoxy carbonyl group, sulfo
group, nitro group, cyano group, optionally substituted alkyl
group, optionally substituted aryl group, optionally substituted
alkoxy group, optionally substituted aryloxy group, optionally
substituted alkyl amino group, optionally substituted aryl amino
group, optionally substituted alkyl sulfonyl group and optionally
substituted aryl sulfonyl group, among which a hydrogen atom,
carboxyl group, alkoxy carbonyl group, optionally substituted alkyl
group and optionally substituted aryl group are preferable.
[0033] The substituent group which may be introduced into the
optionally substituted group includes those groups exemplified for
the general formula (1). Y represents an oxygen atom, sulfur atom,
or --N(R.sup.12)--. R.sup.12 has the same meaning as of R.sup.12 in
the general formula (1), and preferable examples thereof are also
those groups exemplified for the general formula (1). 4
[0034] In the general formula (3) above, R.sup.9 is preferably a
hydrogen atom or an optionally substituted alkyl group among which
a hydrogen atom or a methyl group is preferable because of higher
radical reactivity. R.sup.10 and R.sup.11 independently represent a
hydrogen atom, halogen atom, amino group, dialkyl amino group,
carboxyl group, alkoxy carbonyl group, sulfo group, nitro group,
cyano group, optionally substituted alkyl group, optionally
substituted aryl group, optionally substituted alkoxy group,
optionally substituted aryloxy group, optionally substituted
alkylamino group, optionally substituted arylamino group,
optionally substituted alkyl sulfonyl group and optionally
substituted aryl sulfonyl group, among which a hydrogen atom,
carboxyl group, alkoxy carbonyl group, optionally substituted alkyl
group and optionally substituted aryl group are preferable because
of higher radical reactivity.
[0035] The substituent group which may be introduced into the
optionally substituted group includes those groups exemplified for
the general formula (1). Z represents an oxygen atom, sulfur atom,
--N(R.sup.12)--, or optionally substituted phenylene group.
R.sup.12 has the same meaning as that of R.sup.12 in the general
formula (1), and preferable examples thereof are also those groups
exemplified in the general formula (1).
[0036] The backbone structure of the specific alkali-soluble
polymer according to the invention is preferably
poly(meth)acryl-based resin, polystyrene-based resin,
polyurethane-based resin, and polyvinyl resin modified with acetal,
among which polystyrene-based resin is particularly preferable
because of higher glass transition temperature. As used herein, the
polystyrene-based resin refers to that having a polymer structure
containing units derived from styrene derivatives, and for higher
glass transition temperature, the polystyrene-based resin contains
preferably at least 30 mol-% (more preferably at least 50 mol-%)
units derived from styrene derivatives, relative to the total units
(100%) of the polymer. Further, the side-chain structures
represented by the general formulae (1), (2) and (3) are linked
preferably to the styrene derivative units.
[0037] The structure of the unit derived from a styrene derivative
is preferably a structure represented by the general formula (4):
5
[0038] in which R.sup.13 represents a hydrogen atom or a C.sub.1-5
alkyl group.
[0039] In this formula, R.sup.14 to R.sup.18 independently
represent a monovalent organic group, preferably a hydrogen atom,
halogen atom, alkyl group, aromatic group, heterocyclic group,
hydroxyl group, alkoxy group, aryloxy group, mercapto group, alkyl
thio group, aryl thio group, alkyl dithiol group, aryl dithio
group, amino group, N-alkyl amino group, N,N-dialkyl amino group,
N-aryl amino group, N,N-diaryl amino group, N-alkyl-N-aryl amino
group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy
group, N-aryl carbamoyloxy group, N,N-dialkyl carbamoyloxy group,
N,N-diaryl carbamoyloxy group, N-alkyl-N-aryl carbamoyloxy group,
alkyl sulfoxy group, aryl sulfoxy group, acyl thio group, acyl
amino group, N-alkyl acyl amino group, N-aryl acyl amino group,
ureido group, N-alkyl ureido group, N,N-dialkyl ureido group,
N-aryl ureido group, N,N-diaryl ureido group, N-alkyl-N-aryl ureido
group, N-alkyl ureido group, N-aryl ureido group, N-alkyl-N-alkyl
ureido group, N-alkyl-N-aryl ureido group, N,N-dialkyl-N-alkyl
ureido group, N,N-dialkyl-N-aryl ureido group, N-aryl-N-alkyl
ureido group, N-aryl-N-aryl ureido group, N,N-diaryl-N-alkyl ureido
group, N,N-diaryl-N-aryl ureido group, N-alkyl-N-aryl-N-alkyl
ureido group, N-alkyl-N-aryl-N-aryl ureido group, alkoxy carbonyl
amino group, aryloxy carbonyl amino group, N-alkyl-N-alkoxycarbonyl
amino group, N-alkyl-N-aryloxy carbonyl amino group,
N-aryl-N-alkoxycarbonyl amino group, N-aryl-N-aryloxycarbonyl amino
group, formyl group, acyl group, carboxyl group and its conjugated
basic group (referred to hereinafter as carboxylate), alkoxy
carbonyl group, aryloxy carbonyl group, carbamoyl group, N-alkyl
carbamoyl group, N,N-dialkyl carbamoyl group, N-aryl carbamoyl
group, N,N-diaryl carbamoyl group, N-alkyl-N-aryl carbamoyl group,
alkyl sulfinyl group, aryl sulfinyl group, alkyl sulfonyl group,
aryl sulfonyl group, sulfo group (--SO.sub.3H) and its conjugated
base (referred to hereinafter as sulfonate group); and
[0040] alkoxy sulfonyl group, aryloxy sulfonyl group, sulfinamoyl
group, N-alkyl sulfinamoyl group, N,N-dialkyl sulfinamoyl group,
N-aryl sulfinamoyl group, N,N-diaryl sulfinamoyl group,
N-alkyl-N-aryl sulfinamoyl group, sulfamoyl group, N-alkyl
sulfamoyl group, N,N-dialkyl sulfamoyl group, N-aryl sulfamoyl
group, N,N-diaryl sulfamoyl group, N-alkyl-N-aryl sulfamoyl group,
N-acyl sulfamoyl group and its conjugated basic group, N-alkyl
sulfonyl sulfamoyl group (--SO.sub.2NHSO.sub.2 (alkyl)) and its
conjugated base, N-aryl sulfonyl sulfamoyl group
(--SO.sub.2NHSO.sub.2 (alkyl)) and its conjugated base, N-alkyl
sulfonyl carbamoyl group (--CONHSO.sub.2 (alkyl) ) and its
conjugated base, N-aryl sulfonyl carbamoyl group (--CONHSO.sub.2
(allyl)) and its conjugated base, alkoxy silyl group
(--Si(Oalkyl).sub.3), aryloxy silyl group (--Si(Oallyl).sub.3),
hydroxylyl group (--Si(OH).sub.3) and its conjugated base,
phosphono group (--PO.sub.3H.sub.2) and is conjugated basic group
(referred to hereinafter as phosphonate group), dialkyl phosphono
group (--PO.sub.3 (alkyl).sub.2) diaryl phosphono group (--PO.sub.3
(aryl).sub.2), alkyl aryl phosphono group (--PO.sub.3 (alkyl)
(aryl)), monoalkyl phosphono group (--PO.sub.3H (alkyl)) and its
conjugated basic group (referred to hereinafter as alkyl
phosphonate group), monoaryl phosphono group (--PO.sub.3H (aryl))
and its conjugated basic group (referred to hereinafter as aryl
phosphonate group), phosphonoxy group (--OPO.sub.3H.sub.2) and its
conjugated basic group (referred to hereinafter as phosphonatoxy
group), dialkyl phosphonoxy group (--OPO.sub.3 (alkyl).sub.2),
diaryl phosphonoxy group (--OPO.sub.3 (aryl).sub.2), alkyl aryl
phosphonoxy group (--OPO.sub.3 (alkyl) (aryl)), monoalkyl
phosphonoxy group (--OPO.sub.3H (alkyl)) and its conjugated basic
group (referred to hereinafter as alkyl phosphonatoxy group),
monoaryl phosphonoxy group (--OPO.sub.3H (aryl)) and its conjugated
basic group (referred to hereinafter as aryl phosphonatoxy group),
cyano group and nitro group.
[0041] The structure in which a side-chain structure selected from
the general formulae (1) to (3) above has been linked to the
styrene derivative unit is preferably a structure represented by
the following formula (5): 6
[0042] In the general formula (5), R.sup.19 represents a hydrogen
atom or a C.sub.1-5 alkyl group. R.sup.20 to R.sup.24 independently
represent a monovalent organic group, at least one of which has a
structure represented by the general formula (1), (2) or (3).
Monovalent organic groups other than the organic groups selected
from the general formulae (1) to (3) include those groups
exemplified above as R.sup.14 to R.sup.18 in the general formula
(4).
[0043] The method of introducing an unsaturated group selected from
the general formulae (1) to (3) to a side chain consisting of
styrene derivative units includes, but is not limited to, the
following methods.
[0044] Synthesis Method 1)
[0045] A method in which one or more radical-polymerizable
compounds represented by the general formula (6) below are
copolymerized with one another, or one or more
radical-polymerizable compounds represented by the general formula
(6) are copolymerized with at least one or more other
radical-polymerizable compounds not having the groups described
above, to synthesize a precursor of the desired polymer compound by
usual radical polymerization, followed by deprotonation thereof
with a base thereby eliminating Z to give the desired polymer
compound.
[0046] A precursor of the polymer compound can be produced by any
methods known in the art, such as suspension polymerization or
solution polymerization. The copolymer may be constituted to be a
block copolymer, random copolymer or graft polymer. 7
[0047] In the general formula (6) above, Ar represents an
optionally substituted styryl group and .alpha.-methyl styryl
group; Z represents an anionic eliminating group; Q represents an
oxygen atom, --NH-- or --NR.sup.4--; R.sup.4 represent a hydrogen
atom or an optionally substituted alkyl group; and A represents a
divalent organic linking group.
[0048] The usable radical-polymerizable compound represented by the
general formula (6) includes, but is not limited to, the compounds
described below: 8
[0049] The base used in deprotonation may be either an inorganic or
organic compound. Preferable examples of the inorganic compound as
the base include sodium hydroxide, potassium hydroxide, sodium
carbonate, sodium bicarbonate, potassium carbonate and potassium
bicarbonate, and preferable examples of the organic compound as the
base include metal alkoxides such as sodium methoxide, sodium
ethoxide and potassium t-butoxide, and organic amine compounds such
as triethyl amine, pyridine, and diisopropyl ethylamine.
[0050] Synthesis Method 2)
[0051] A method in which one or more radical-polymerizable
compounds having functional groups are copolymerized with one
another, or one or more radical-polymerizable compounds having
functional groups are copolymerized with other
radical-polymerizable compound not having the groups described
above, to synthesize a backbone polymer compound (polymer compound
constituting the backbone) by radical polymerization, followed by
reacting the functional groups in its side chains with a
low-molecular compound having the structure of the general formula
(1B) below or the general formula (2) above to give the desired
polymer compound.
[0052] The backbone polymer compound can be produced by any methods
known in the art, such as suspension polymerization or solution
polymerization. The copolymer may be constituted to be a block
copolymer, random copolymer or graft polymer. 9
[0053] In the general formula (1B), R.sup.1 to R.sup.3 have the
same meaning as in the general formula (1) above.
[0054] In the radical-polymerizable compounds having functional
groups, the functional groups include e.g. a hydroxyl group,
carboxyl group, carboxylic halide group, carboxylic anhydride
group, amino group, halogenated alkyl group, isocyanate group,
epoxy group, oxazoline group and oxime group. The
radical-polymerizable compounds having these functional groups
include 4-hydroxy styrene, 3-hydroxymethyl styrene,
4-(2-hydroxyethyl) styrene, 4-chloromethyl styrene, 4-carboxyl
styrene, 4-aminostyrene and 4-methyl aminostyrene.
[0055] Compounds having the groups represented by the general
formula (1B) include e.g. 2-hydroxylethyl acrylate, 2-hydroxyethyl
methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate,
acrylic acid, methacrylic acid, acrylic chloride, methacrylic
chloride, methacrylic anhydride, N,N-dimethyl-2-aminoethyl
methacrylate, 2-chloroethyl methacrylate, 3-bromopropyl acrylate,
6-bromohexyl acrylate, 3-bromopropyl methacrylate, 6-bromohexyl
methacrylate, 2-isocyanate ethyl methacrylate, glycidyl acrylate
and glycidyl methacrylate.
[0056] In the invention, the specific alkali-soluble polymer
compound having the group of formula (2) in a side chain thereof
can be produced by at least one of synthesis methods shown in 3)
and 4) below.
[0057] Synthesis Method 3)
[0058] A method in which one or more radical-polymerizable
compounds having both the unsaturated group represented by the
general formula (2) and an ethylenically unsaturated group more
reactive in addition polymerization than said unsaturated group are
polymerized if necessary with other radical-polymerizable
compounds, to give the polymer compound.
[0059] The radical-polymerizable compound having both the
unsaturated group represented by the general formula (2) and an
ethylenically unsaturated group more reactive in addition
polymerization than said unsaturated group, used in Synthesis
Method 3), includes e.g. 4-aryloxy styrene, 4-(2-aryloxy)ethyl
styrene, 3-aryloxymethyl styrene and 4-(N-allyl) aminostyrene.
[0060] Synthesis Method 4)
[0061] A method in which one or more radical-polymerizable
compounds having a functional group are polymerized to synthesize
the polymer compound which is then reacted with a compound having a
side-chain functional group and the structure shown in the general
formula (2B), to introduce this compound into the polymer compound.
10
[0062] The polymer compound obtained by polymerizing one or more
radical-polymerizable compounds having a functional group includes
e.g. the compounds enumerated above in
[0063] Synthesis Method 2).
[0064] The compound having the structure shown in the general
formula (2B) used in Synthesis Example 4) includes e.g. allyl
bromide, allyl alcohol, allyl amine, diallyl amine, 2-aryloxyethyl
alcohol, 2-chloro-l-butene and allyl isocyanate.
[0065] The specific alkali-soluble polymer compound having, in a
side chain thereof, the group represented by the general formula
(3) in the invention can be synthesized by Synthesis Method 5)
shown below.
[0066] Synthesis Method 5)
[0067] A method in which one or more radical-polymerizable
compounds having a functional group are polymerized to synthesize a
polymer compound and then reacted with a compound having a
side-chain functional group and the structure represented by the
general formula (3B), to introduce this compound into the polymer
compound. 11
[0068] The polymer compound obtained by polymerizing one or more
radical-polymerizable compounds having a functional group include
the compounds exemplified above in Synthesis Method 2).
[0069] The compound having the structure represented by the general
formula (3B) used in Synthesis Method 5 includes e.g.
2-hydroxyethyl monovinyl ether, 4-hydroxybutyl monovinyl ether,
diethylene glycol monovinyl ether, 2-chloroethyl vinyl ether,
1-aminoethyl vinyl ether, 4-hydroxystyrene, 3-hydroxymethyl
styrene, 4-(2-hydroxyethyl) styrene, 4-chloromethyl styrene,
4-carboxyl styrene, 4-aminostyrene and 4-methylaminostyrene.
[0070] The specific alkali water- soluble polymer may also be
obtained by using one of these production methods (synthesis
methods) or a combination thereof.
[0071] Moreover, the structural unit having a side chain
"carbon-carbon doublebond" represented by general formulae (1) to
(3) may contain materials other than the styrene derivative
structural unit represented by formula (5). Specific examples
thereof include those disclosed in Japanese Patent Application No.
2000-249569.
[0072] The resultant specific alkali water-soluble polymers can be
contained alone or as a combination thereof in the image forming
material of the invention.
[0073] The content of "a carbon-carbon double bond of side chain"
is preferably set to not less than 1.5 meq/g, more preferably 1.5
to 7.0 meq/g, when represented by equivalent number per polymer
compound of 1 gram. If the content is lower than 1.5 meq/g, the
curing property becomes insufficient, failing to provide sufficient
image intensity. If the content is higher than 7.0 meq/g, the
storage stability is lowered.
[0074] In order to set the glass transition temperature higher, it
is effective to allow the polymer compound of the present invention
to contain at least one amide group in its side chain. Here, the
side chain amide group is also effective to improve properties such
as resistance to printing and a non-image-portion removing
property.
[0075] A preferable side chain amide group is represented by the
following formula (1): 12
[0076] R.sup.1 and R.sup.2 independently represent a monovalent
organic group. Preferably, these represent a hydrogen atom or an
optionally substituted alkyl group, alkenyl group, alkynyl group,
aryl group, heterocyclic group or alicyclic group, and R.sup.1 and
R.sup.2 may be bonded to form a ring structure.
[0077] Examples of alkyl group include a straight-chain, a branched
and a cyclic alkyl group containing 1 to 20 carbon atoms; and
specific examples include methyl group, ethyl group, propyl group,
butyl group, pentyl group, hexyl group, heptyl group, octyl group,
nonyl group, decyl group, undecyl group, dodecyl group, tridecyl
group, hexadecyl group, octadecyl group, eicosyl group, isopropyl
group, isobutyl group, s-butyl group, t-butyl group, isopentyl
group, neopentyl group, 1-methylbutyl group, isohexyl group,
2-ethylhexyl group, 2-methylhexyl group, cyclohexyl group,
cyclopentyl group and 2-norbornyl group. Among these, a
straight-chain alkyl group containing 1 to 12 carbon atoms, a
branched alkyl group containing 3 to 12 carbon atoms and a
ring-shaped alkyl group containing 5 to 10 carbon atoms are more
preferably used.
[0078] With respect to the substituents of the substituted alkyl
group, groups of monovalent non-metal atoms except for hydrogen
atom are used, and preferable examples thereof include: halogen
atom (--F, --Br, --Cl, --I), hydroxyl group, alkoxy group, aryloxy
group, mercapto group, alkyl thio group, aryl thio group, alkyl
dithio group, aryl dithio group, amino group, N-alkyl amino group,
N,N-dialkyl amino group, N-aryl amino group, N,N-diaryl amino
group, N-alkyl-N-aryl amino group, acyloxy group, carbamoyloxy
group, N-alkyl carbamoyloxy group, N-aryl carbamoyloxy group,
N,N-dialkyl carbamoyloxy group, N,N-diaryl carbamoyloxy group,
N-alkyl-N-aryl carbamoyloxy group, alkyl sulfoxy group, aryl
sulfoxy group, acyl thio group, acyl amino group, N-alkyl acyl
amino group, N-aryl acyl amino group, ureido group, N'-alkyl ureido
group, N',N'-dialkyl ureido group, N'-aryl ureido group,
N',N'-diaryl ureido group, N'-alkyl-N'-aryl ureido group, N-alkyl
ureido group, N-aryl ureido group, N'-alkyl-N-alkyl ureido group,
N'-alkyl-N-aryl ureido group, N',N'-dialkyl-N-alkyl ureido group,
N',N'-dialkyl-N-aryl ureido group, N'-aryl-N-alkyl ureido group,
N'-aryl-N-aryl ureido group, N',N'-diaryl-N-alkyl ureido group,
N',N'-diaryl-N-aryl ureido group, N'-alkyl-N'-aryl-N-alkyl ureido
group, N'-alkyl-N'-aryl-N-aryl ureido group, alkoxy carbonyl amino
group, aryloxy carbonyl amino group, N-alkyl-N-alkoxy carbonyl
amino group, N-alkyl-N-aryloxy carbonyl amino group,
N-aryl-N-alkoxy carbonyl amino group, N-aryl-N-aryloxy carbonyl
amino group, formyl group, acyl group, carboxyl group, alkoxy
carbonyl group, aryloxy carbonyl group, carbamoyl group, N-alkyl
carbamoyl group, N,N-dialkyl carbamoyl group, N-aryl carbamoyl
group, N,N-diaryl carbamoyl group, N-alkyl-N-aryl carbamoyl group,
alkyl sulfinyl group, aryl sulfinyl group, alkyl sulfonyl group,
aryl sulfonyl group, sulfo group (--SO.sub.3H) and its conjugated
base (referred to hereinafter as sulfonate group); alkoxy sulfonyl
group, aryloxy sulfonyl group, sulfinamoyl group, N-alkyl
sulfinamoyl group, N,N-dialkyl sulfinamoyl group, N-aryl
sulfinamoyl group, N,N-diaryl sulfinamoyl group, N-alkyl-N-aryl
sulfinamoyl group, sulfamoyl group, N-alkyl sulfamoyl group,
N,N-dialkyl sulfamoyl group, N-aryl sulfamoyl group, N,N-diaryl
sulfamoyl group, N-alkyl-N-aryl sulfamoyl group, phosphono group
(--PO.sub.3H.sub.2) and its conjugated basic group (referred to
hereinafter as phosphonate group), dialkyl phosphono group
(--PO.sub.3 (alkyl).sub.2: alkyl=alkyl group, the same is true in
the following description), diaryl phosphono group (--PO.sub.3
(aryl).sub.2: aryl=aryl group, the same is true in the following
description) alkyl aryl phosphono group (--PO, (alkyl) (aryl)),
monoalkyl phosphono group (13 PO.sub.3 (alkyl) ) and its conjugated
basic group (referred to hereinafter as alkyl phosphonate group)
monoaryl phosphono group (--PO.sub.3H (aryl)) and its conjugated
basic group (referred to hereinafter as aryl phosphonate group),
phosphonoxy group (--OPO.sub.3H.sub.2) and its conjugated basic
group (referred to hereinafter as phosphonatoxy group), dialkyl
phosphonoxy group (--OPO.sub.3H (alkyl),.sub.2), diaryl phosphonoxy
group (--OPO.sub.3 (aryl).sub.2), alkyl aryl phosphonoxy group
(--OPO.sub.3 (alkyl) (aryl)), monoalkyl phosphonoxy group
(--OPO.sub.3H (alkyl) ) and its conjugated basic group (referred to
hereinafter as alkyl phosphonatoxy group), monoaryl phosphonoxy
group (--OPO.sub.3H (aryl)) and its conjugated basic group
(referred to hereinafter as aryl phosphonatoxy group), cyano group,
nitro group, aryl group, alkenyl group, alkynyl group, heterocyclic
group, silyl group, etc.
[0079] With respect to the specific examples of alkyl groups in
these substituents, the aforementioned alkyl groups are listed, and
specific examples of aryl groups include: phenyl group, biphenyl
group, naphthyl group, tolyl group, xylyl group, mesityl group,
cumenyl group, chlorophenyl group, bromophenyl group, chloromethyl
phenyl group, hydroxyl phenyl group, methoxy phenyl group, ethoxy
phenyl group, phenoxy phenyl group, acetoxyphenyl group, benzoyloxy
phenyl group, methyl thio phenyl group, phenyl thio phenyl group,
methyl amino phenyl group, dimethyl amino phenyl group, acetyl
amino phenyl group, carboxy phenyl group, methoxy carbonyl phenyl
group, ethoxyphenyl carbonyl group, phenoxy carbonyl phenyl group,
N-phenyl carbamoyl phenyl group, cyanophenyl group, sulfophenyl
group, sulfonate phenyl group, phosphono phenyl group, phosphonate
phenyl group, etc.
[0080] Moreover, examples of the alkenyl group include: vinyl
group, 1-propenyl group, 1-butenyl group, cinnamyl group,
2-chloro-1-ethenyl group, etc. are listed, and examples of the
alkynyl group include ethenyl group, 1-propynyl group, 1-butynyl
group, trimethylsilyl ethenyl group, etc.
[0081] With respect to R01 in the acyl group (R01CO--), examples
thereof include hydrogen atom, and the above-mentioned alkyl groups
and aryl groups. Among these substituents, more preferable examples
include: halogen atom (--F, --Br, --Cl, --I), alkoxy group, aryloxy
group, alkyl thio group, aryl thio group, N-alkyl amino group,
N,N-dialkyl amino group, acyloxy group, N-alkyl carbamoyloxy group,
N-aryl carbamoyloxy group, acyl amino group, formyl group, acyl
group, carboxyl group, alkoxy carbonyl group, aryloxy carbonyl
group, carbamoyl group, N-alkyl carbamoyl group, N,N-dialkyl
carbamoyl group, N-aryl carbamoyl group, N-alkyl-N-aryl carbamoyl
group, sulfo group, sulfonate group, sulfamoyl group, N-alkyl
sulfamoyl group, N,N-dialkyl sulfamoyl group, N-aryl sulfamoyl
group, N-alkyl-N-aryl sulfamoyl group, phosphono group, phosphonate
group, dialkyl phosphono group, diaryl phosphono group, monoalkyl
phosphono group, alkyl phosphonate group, monoaryl phosphono group,
aryl phosphono group, phosphonoxy group, phosphonatoxy group, aryl
group, alkenyl group, etc.
[0082] Examples of heterocyclic groups include pyridyl group,
piperidyl group, etc. Examples of silyl groups include trimethyl
silyl group, etc.
[0083] Here, with respect to alkylene groups in the substituted
alkyl group, those from which any one of hydrogen atoms on the
above-mentioned alkyl group containing 1 to 20 carbon atoms is
excluded to form divalent organic residues, and preferable examples
include straight-chain alkylene groups containing 1 to 12 carbon
atoms, branched alkylene groups containing 3 to 12 carbon atoms and
cyclic alkylene groups containing 5 to 10 carbon atoms. Preferable
examples of substituted alkyl groups obtained by combining these
substituents and alkylene groups include: chloromethyl group,
bromomethyl group, 2-chloroethyl group, trifluoro methyl group,
methoxymethyl group, isopropoxy methyl group, butoxy methyl group,
s-butoxy butyl group, methoxy ethoxy ethyl group, aryloxy methyl
group, phenoxy methyl group, methyl thio methyl group, tolyl thio
methyl group, pyridyl methyl group, tetramethyl piperidinyl methyl
group, N-acetyl tetramethyl piperidinyl methyl group, trimethyl
silyl methyl group, methoxy ethyl group, ethyl amino ethyl group,
diethyl amino propyl group, morpholinopropyl group, acetyloxy
methyl group, benzoyloxy methyl group, N-cyclohexyl carbamoyloxy
ethyl group, N-phenyl carbamoyloxy ethyl group, acetyl amino ethyl
group, N-methyl benzoyl amino propyl group, 2-oxoethyl group,
2-oxopropyl group, carboxy propyl group, methoxy carbonyl ethyl
group, allyloxy carbonyl butyl group, chlorophenoxy carbonyl methyl
group, carbamoyl methyl group, N-methyl carbamoyl ethyl group,
N,N-dipropyl carbamoyl methyl group, N-(methoxy phenyl) carbamoyl
ethyl group, N-methyl-N-(sulfonyl) carbamoyl methyl group, sulfo
butyl group, sulfonate butyl group, sulfamoyl butyl group, N-ethyl
sulfamoylmethyl group, N,N-dipropyl sulfamoylpropyl group, N-tolyl
sulfamoyl propyl group, N-methyl-N-(phosphono phenyl) sulfamoyl
octyl group, phosphono butyl group, phosphonate hexyl group,
diethyl phosphono butyl group, diphenyl phosphono propyl group,
methyl phosphono butyl group, methyl phosphonate butyl group, tolyl
phosphono hexyl group, tolyl phosphonate hexyl group, phosphonoxy
propyl group, phosphonatoxy butyl group, benzyl group, phenetyl
group, a-methyl benzyl group, 1-methyl-1-phenyl ethyl group,
p-methyl benzyl group, cinnamyl group, allyl group, 1-propenyl
methyl group, 2-butenyl group, 2-methyl allyl group, 2-methyl
propenyl methyl group, 2-propynyl group, 2-butynyl group, 3-butynyl
group, etc.
[0084] Next, with respect to aryl groups serving as R.sup.1 to
R.sup.7, those in which one to three benzene rings form a condensed
ring and those in which a benzene ring and a 5-member unsaturated
ring form a condensed ring are listed, and specific examples
thereof include: phenyl group, naphthyl group, anthryl group,
phenanthryl group, indenyl group, acetonaphthyl group, fluorenyl
group, etc., and among these, phenyl group and naphthyl group are
preferably used.
[0085] With respect to substituted aryl groups, those in which a
group that consists of monovalent non-metal atomic group except for
hydrogen atoms is placed on ring-forming carbon atoms of the
above-mentioned aryl group as a substituent group are used.
Examples of preferable substituents include the above-mentioned
alkyl groups, substituted alkyl groups and those described earlier
as substituents in substituted alkyl groups. Specific examples of
preferable substituted aryl groups include: biphenyl group, tolyl
group, xylyl group, mesityl group, cummenyl group, chlorophenyl
group, bromophenyl group, fluorophenyl group, chloromethyl phenyl
group, trifluoro methyl phenyl group, hydroxy phenyl group, methoxy
phenyl group, methoxyethoxy phenyl group, allyloxy phenyl group,
phenoxy phenyl group, methyl thio phenyl group, tolyl thio phenyl
group, ethyl amino phenyl group, diethyl amino phenyl group,
morpholino phenyl group, acetyl oxyphenyl group, benzoyl oxyphenyl
group, N-cyclohexyl carbamoyl oxyphenyl group, N-phenyl carbamoyl
oxyphenyl group, acetyl aminophenyl group, N-methyl benzoyl amino
phenyl group, carboxy phenyl group, methoxy carbonyl phenyl group,
allyloxy carbonyl phenyl group, chlorophenoxy carbonyl phenyl
group, carbamoyl phenyl group, N-methyl carbamoyl phenyl group,
N,N-dipropyl carbamoyl phenyl group, N-(methoxyphenyl) carbamoyl
phenyl group, N-methyl-N-(sulfonyl) carbamoyl phenyl group,
sulfophenyl group, sulfonate phenyl group, sulfamoyl phenyl group,
N-ethylsulfamoyl phenyl group, N,N-dipropyl sulfamoyl phenyl group,
N-tolyl sulfamoyl phenyl group, N-methyl-N-(phosphono phenyl)
sulfamoyl phenyl group, phosphono phenyl group, phosphonate phenyl
group, diethyl phosphono phenyl group, diphenyl phosphono phenyl
group, methyl phosphono phenyl group, methyl phosphonate phenyl
group, tolyl phosphono phenyl group, tolyl phosphonate phenyl
group, allyl phenyl group, 1-propenyl methyl phenyl group,
2-butenyl phenyl group, 2-methyl allyl phenyl group, 2-methyl
propenyl phenyl group, 2-propynyl phenyl group, 2-butynyl phenyl
group, 3-butynyl phenyl group, etc.
[0086] With respect to the alkenyl group, substituted alkenyl
group, alkynyl group and substituted alkynyl group (--C
(R02).dbd.C(R03)(R04), and --C.ident.C(R05), those groups in which
R02, R03, R04, R05 are constituted by a monovalent non-metal atomic
group maybe used. Examples of preferable R02, R03, R04 and R05
include hydrogen atom, halogen atom, alkyl group, substituted alkyl
group, aryl group and substituted aryl group, etc. Specific
examples of these include the same materials as described in the
above-mentioned examples. More preferable examples of R02, R03, R04
and R05 include hydrogen atom, halogen atom and straight-chain,
branched and cyclic alkyl groups containing 1 to 10 carbon atoms.
With respect to preferable alkenyl group, substituted alkenyl
group, alkynyl group and substituted alkynyl group represented by
R.sup.1 to R.sup.7, examples thereof include vinyl group,
1-propenyl group, 1-butenyl group, 1-pentenyl group, 1-hexenyl
group, 1-octenyl group, 1-methyl-1-propenyl group,
2-methyl-1-propenyl group, 2-methyl-1-butenyl group,
2-phenyl-1-ethenyl group, 2-chloro-1-ethenyl group, ethenyl group,
1-propynyl group, 1-butynyl group and phenyl ethenyl group.
[0087] With respect to rings formed by joining R.sup.1 and R.sup.2
to each other in general formula (1), examples thereof include
morpholine, piperazine, pyrrolidine, pyrrole and indoline. These
may be substituted by the above-mentioned substituents. Among
these, those having an aliphatic ring are preferably used.
[0088] With respect to R.sup.1 and R.sup.2 in formula (1), hydrogen
atom, alkyl group, alkenyl group, aryl group are preferably used.
Moreover, R.sup.1 and R2 may preferably form an aliphatic ring.
[0089] More preferable examples include acrylamides such as
acrylamide and N-alkyl acrylamide (for example, N-methyl
acrylamide, N-ethyl acrylamide, N-propyl acrylamide, N-isopropyl
acrylamide, morpholyl acrylamide, piperidyl acrylamide, N-butyl
acrylamide, N-sec-butyl acrylamide, N-t-butyl acrylamide, N-hexyl
acrylamide, N-cyclohexyl acrylamide, N-phenyl acrylamide,
N-naphthyl acrylamide, N-hydroxymethyl acrylamide, N-hydroxyethyl
acrylamide, N-allyl acrylamide, N-propargyl acrylamide, 4-hydroxy
phenyl acrylamide, 2-hydroxy phenyl acrylamide, N,N-dimethyl
acrylamide, N,N-diethyl acrylamide, N,N-dipropyl acrylamide,
N,N-diisopropyl acrylamide, N,N-dibutyl acrylamide,
N,N-di-sec-butyl acrylamide, N,N-di-t-butyl acrylamide, N,N-dihexyl
acrylamide, N,N-dicyclohexyl acrylamide, N,N-phenyl acrylamide,
N,N-dihydroxyethyl acrylamide, N,N-diallyl acrylamide,
N,N-dipropargyl acrylamide etc.,
[0090] methacrylamides such as methacrylamide and N-alkyl
methacrylamide (for example, N-methyl methacrylamide, N-ethyl
methacrylamide, N-propyl methacrylamide, N-isopropyl
methacrylamide, morpholyl methacrylamide, piperidyl methacrylamide,
N-butyl methacrylamide, N-sec-butyl methacrylamide, N-t-butyl
methacrylamide, N-hexyl methacrylamide, N-cyclohexyl
methacrylamide, N-phenyl methacrylamide, N-naphthyl methacrylamide,
N-hydroxymethyl methacrylamide, N-hydroxyethyl methacrylamide,
N-allyl methacrylamide, N-propargyl methacrylamide, 4-hydroxyphenyl
methacrylamide, 2-hydroxyphenyl methacrylamide, N,N-dimethyl
methacrylamide, N,N-diethyl methacrylamide, N,N-dipropyl
methacrylamide, N,N-diisopropyl methacrylamide, N,N-dibutyl
methacrylamide, N,N-di-sec-butyl methacrylamide, N,N-di-t-butyl
methacrylamide, N,N-dihexyl methacrylamide, N,N-dicyclohexyl
methacrylamide, N,N-phenyl methacrylamide, N,N-dihydroxyethyl
methacrylamide, N,N-diallyl methacrylamide, N,N-dipropargyl
methacrylamide etc.).
[0091] For the purpose of improving various properties such as
image strength, the specific alkali water-soluble polymer of the
invention can be copolymerized in a preferable embodiment not only
with radical-polymerizable compounds having the above-described
specific functional groups but also with other
radical-polymerizable compounds unless the effect of the invention
is hindered.
[0092] The radical-polymerizable compounds copolymerizable with the
specific alkali water-soluble polymer in the invention include e.g.
radical-polymerizable compounds selected from acrylic ester,
methacrylates, acrylamides, methacrylamides, styrene and analogues
thereof, acrylonitriles, and methacrylonitriles.
[0093] Specifically, the radical-polymerizable compounds include
for example:
[0094] acrylic ester such as alkyl acrylate whose alkyl group
preferably contains 1 o 20 carbon atoms (specifically, for example,
benzyl acrylate, 4-biphenyl acrylate, butyl acrylate, sec-butyl
acrylate, t-butyl acrylate, 4-t-butylphenyl acrylate,
4-chlorophenyl acrylate, pentachlorophenyl acrylate, 4-cyanobenzyl
acrylate, cyanomethyl acrylate, cyclohexyl acrylate, 2-ethoxyethyl
acrylate, ethyl acrylate, 2-ethylhexyl acrylate, heptyl acrylate,
hexyl acrylate, isoboronyl acrylate, isopropyl acrylate, methyl
acrylate, 3,5-dimethyl adamantyl acrylate, 2-naphthyl acrylate,
neopentyl acrylate, octyl acrylate, phenetyl acrylate, phenyl
acrylate, propyl acrylate, tolyl acrylate, amyl acrylate,
tetrahydrofurfuryl acrylate, 2-hydroxyethyl acrylate,
3-hydroxypropyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl
acrylate, 5-hydroxypentyl acrylate, allyl acrylate, 2-aryloxyethyl
acrylate, propargyl acrylate etc.),
[0095] methacrylates such as alkyl methacrylate whose alkyl group
preferably contains 1 to 20 carbon atoms (for example, benzyl
methacrylate, 4-biphenyl methacrylate, butyl methacrylate,
sec-butyl methacrylate, t-butyl methacrylate, 4-t-butylphenyl
methacrylate, 4-chlorophenyl methacrylate, pentachlorophenyl
methacrylate, 4-cyanophenyl methacrylate, cyanomethyl methacrylate,
cyclohexyl methacrylate, 2-ethoxyethyl methacrylate, ethyl
methacrylate, 2-ethylhexyl methacrylate, heptyl methacrylate, hexyl
methacrylate, isoboronyl methacrylate, isopropyl methacrylate,
methyl methacrylate, 3,5-dimethyl adamantyl methacrylate,
2-naphthyl methacrylate, neopentyl methacrylate, octyl
methacrylate, phenetyl methacrylate, phenyl methacrylate, propyl
methacrylate, tolyl methacrylate, amyl methacrylate,
tetrahydrofurfuryl methacrylate, 2-hydroxyethyl methacrylate,
3-hydroxypropyl methacrylate, 2-hydroxypropyl methacrylate,
4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, allyl
methacrylate, 2-aryloxyethyl methacrylate, propargyl methacrylate
etc.),
[0096] acrylamides such as acrylamide and N-alkyl acrylamide (for
example, N-methyl acrylamide, N-ethyl acrylamide, N-propyl
acrylamide, N-isopropyl acrylamide, morpholyl acrylamide, piperidyl
acrylamide, N-butyl acrylamide, N-sec-butyl acrylamide, N-t-butyl
acrylamide, N-hexyl acrylamide, N-cyclohexyl acrylamide, N-phenyl
acrylamide, N-naphthyl acrylamide, N-hydroxymethyl acrylamide,
N-hydroxyethyl acrylamide, N-allyl acrylamide, N-propargyl
acrylamide, 4-hydroxy phenyl acrylamide, 2-hydroxy phenyl
acrylamide, N,N-dimethyl acrylamide, N,N-diethyl acrylamide,
N,N-dipropyl acrylamide, N,N-diisopropyl acrylamide, N,N-dibutyl
acrylamide, N,N-di-sec-butyl acrylamide, N,N-di-t-butyl acrylamide,
N,N-dihexyl acrylamide, N,N-dicyclohexyl acrylamide, N,N-phenyl
acrylamide, N,N-dihydroxyethyl acrylamide, N,N-diallyl acrylamide,
N,N-dipropargyl acrylamide etc.,
[0097] methacrylamides such as methacrylamide and N-alkyl
methacrylamide (for example, N-methyl methacrylamide, N-ethyl
methacrylamide, N-propyl methacrylamide, N-isopropyl
methacrylamide, morpholyl methacrylamide, piperidyl methacrylamide,
N-butyl methacrylamide, N-sec-butyl methacrylamide, N-t-butyl
methacrylamide, N-hexyl methacrylamide, N-cyclohexyl
methacrylamide, N-phenyl methacrylamide, N-naphthyl methacrylamide,
N-hydroxymethyl methacrylamide, N-hydroxyethyl methacrylamide,
N-allyl methacrylamide, N-propargyl methacrylamide, 4-hydroxyphenyl
methacrylamide, 2-hydroxyphenyl methacrylamide, N,N-dimethyl
methacrylamide, N,N-diethyl methacrylamide, N,N-dipropyl
methacrylamide, N,N-diisopropyl methacrylamide, N,N-dibutyl
methacrylamide, N,N-di-sec-butyl methacrylamide, N,N-di-t-butyl
methacrylamide, N,N-dihexyl methacrylamide, N,N-dicyclohexyl
methacrylamide, N,N-phenyl methacrylamide, N,N-dihydroxyethyl
methacrylamide, N,N-diallyl methacrylamide, N,N-dipropargyl
methacrylamide etc.), and
[0098] styrene and analogues thereof such as alkyl styrene (for
example, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl
styrene, diethyl styrene, isopropyl styrene, butyl styrene, hexyl
styrene, cyclohexyl styrene, decyl styrene, benzyl styrene,
chloromethyl styrene, trifluoromethyl styrene, ethoxy methyl
styrene, acetoxy methyl styrene etc.), alkoxy styrene (for example,
methoxy styrene, 4-methoxy-3-methyl styrene, dimethoxy styrene
etc.), halogen styrene (for example, chlorostyrene,
dichlorostyrene, trichlorostyrene, tetrachlorostyrene,
pentachlorostyrene, bromostyrene, dibromostyrene, iodostyrene,
fluorostyrene, trifluorostyrene, 2-bromo-4-trifluoromethyl styrene,
4-fluoro-3-trifluoromethyl styrene etc.), acrylonitrile,
methacrylonitrile etc.
[0099] Preferably used among these radical-polymerizable compounds
are methacrylates, acrylamides, methacrylamides, and styrene and
analogues thereof, and particularly preferably used are benzyl
methacrylate, t-butyl methacrylate, 4-t-butylphenyl methacrylate,
pentachlorophenyl methacrylate, 4-cyanophenyl methacrylate,
cyclohexyl methacrylate, ethyl methacrylate, 2-ethylhexyl
methacrylate, isoboronyl methacrylate, isopropyl methacrylate,
methyl methacrylate, 3,5-dimethyl adamantyl methacrylate,
2-naphthyl methacrylate, neopentyl methacrylate, phenyl
methacrylate, tetrahydrofurfuryl methacrylate, 2-hydroxyethyl
methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxypropyl
methacrylate, allyl methacrylate,
[0100] acrylamide, N-methyl acrylamide, N-isopropyl acrylamide,
morpholyl acrylamide, piperidyl acrylamide, N-t-butyl acrylamide,
N-cyclohexyl acrylamide, N-phenyl acrylamide, N-naphthyl
acrylamide, N-hydroxymethyl acrylamide, N-hydroxyethyl acrylamide,
N-allyl acrylamide, 4-hydroxyphenyl acrylamide, 2-hydroxyphenyl
acrylamide, N,N-dimethyl acrylamide, N,N-diisopropyl acrylamide,
N,N-di-t-butyl acrylamide, N,N-dicyclohexyl acrylamide, N,N-phenyl
acrylamide, N,N-dihydroxyethyl acrylamide, N,N-diallyl
acrylamide,
[0101] methacrylamide, N-methyl methacrylamide, N-isopropyl
methacrylamide, morpholyl methacrylamide, piperidyl methacrylamide,
N-t-butyl methacrylamide, N-cyclohexyl methacrylamide, N-phenyl
methacrylamide, N-naphthyl methacrylamide, N-hydroxymethyl
methacrylamide, N-hydroxyethyl methacrylamide, N-allyl
methacrylamide, 4-hydroxyphenyl methacrylamide, 2-hydroxyphenyl
methacrylamide, N,N-dimethyl methacrylamide, N,N-diisopropyl
methacrylamide, N,N-di-t-butyl methacrylamide, N,N-dicyclohexyl
methacrylamide, N,N-phenyl methacrylamide, N, N-dihydroxyethyl
methacrylamide, N,N-diallyl methacrylamide,
[0102] styrene, methyl styrene, dimethyl styrene, trimethyl
styrene, isopropyl styrene, butyl styrene, cyclohexyl styrene,
chloromethyl styrene, trifluoromethyl styrene, ethoxymethyl
styrene, acetoxymethyl styrene, methoxy styrene, 4-methoxy-3-methyl
styrene, chlorostyrene, dichlorostyrene, trichlorostyrene,
tetrachlorostyrene, pentachlorostyrene, bromostyrene,
dibromostyrene, iodostyrene, fluorostyrene, trifluorostyrene,
2-bromo-4-trifluoromethyl styrene and 4-fluoro-3-trifluoromethyl
styrene.
[0103] These can be used alone or in combination thereof, and the
content of these copolymerizable components is 0 to 90 mol-%,
particularly preferably 0 to 60 mol-%. When the content is higher
than 60 mol-%, the cured film is poor in strength.
[0104] The specific alkali water-soluble polymer according to the
invention may be copolymerized with radical-polymerizable compounds
having an acid group, in order to improve various performances such
as an ability to remove the non-image portion. Examples of such
acid groups include a carboxylic acid group, sulfonic acid group,
phosphoric acid group and phenolic hydroxyl group, particularly
preferably a carboxylic acid group and phenolic hydroxyl group. The
radical-polymerizable compound having a carboxylic acid group
includes e.g. acrylic acid, methacrylic acid, itaconic acid,
crotonic acid, isocrotonic acid, maleic acid and p-carboxyl
styrene, among which acrylic acid, methacrylic acid and p-carboxy
styrene are particularly preferable.
[0105] The radical-polymerizable compound having a phenolic
hydroxyl group includes 4-hydroxy styrene.
[0106] These can be used alone or in combination thereof, and the
content of these copolymerizable components is preferably 0 to 50
mol-%, particularly preferably 0 to 40 mol-% from the viewpoint of
preventing the strength of an image from being damaged by
development with an aqueous alkaline solution. When the content is
higher than40 mol-%, the strength of an image is easily damaged by
development with an aqueous alkaline solution.
[0107] The solvent used for synthesis of such polymer compounds
includes e.g. ethylene dichloride, cyclohexanone, methyl ethyl
ketone, acetone, methanol, ethanol, propanol, butanol, ethylene
glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxy
ethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate,
N,N-dimethyl formamide, N,N-dimethyl acetamide, dimethyl sulfoxide,
toluene, ethyl acetate, methyl lactate and ethyl lactate.
[0108] These solvents may be used alone or as a mixture
thereof.
[0109] The weight average molecular weight of the polymer compound
used in the image recording material of the present invention is
preferably 6,000 or more, more preferably in the range of 50,000 to
200,000. If the molecular weight is lower than 6,000, the glass
transition temperature is lowered, and the image intensity becomes
insufficient, resulting in an undesired state. If the molecular
weight is higher than 200,000, the development performance is
lowered.
[0110] Further, the specific alkali water-soluble polymer according
to the invention may also contain unreacted monomers. In this case,
the ratio of the monomers to the polymer compound is desirably 15%
by weight or less.
[0111] The polymer compound according to the invention may be used
alone or in combination thereof. In this case, the amount of other
polymer compounds not included in (A) specific alkali water-soluble
polymer according to the invention is 80% by weight or less, more
preferably 50% by weight or less in the polymer compound.
[0112] The solids content of (A) specific alkali-soluble polymer in
the image recording material of the invention is about 5 to 95% by
weight, preferably about 10 to 85% by weight. When the content is
lower than 5% by weight, the image portion where an image has been
formed is poor in strength. On the other hand, when the content is
higher than 95% by weight, no image is formed.
[0113] (B) Light-heat Converting Agent
[0114] The image recording material of the invention is used in
recording by light exposure in heat mode, typically by a laser
emitting infrared rays, so use of a light-heat converting agent is
essential. The light-heat converting agent has the function of
absorbing a light at a predetermined wavelength to convert it into
heat. By the heat thus generated, component (C) described later,
that is, a compound forming radicals upon heat-mode exposure to
light at a wavelength that can be absorbed by (B) light-heat
exchanging agent is decomposed to generate radicals.
[0115] The light-heat converting agent used in the invention can be
used without particular limitation to the absorption wavelength
range insofar as the light-heat converting agent generates heat
upon absorption of light energy irradiation used in recording. From
the viewpoint of compatibility thereof with an easily available
high-energy laser, the light-heat converting agent used in the
invention is particularly preferably an infrared ray-absorbing dye
or pigment having the absorption maximum in wavelengths between 760
to 1200 nm.
[0116] The dye may be any one of commercial dyes including known
dyes described in e.g. "Senryo Binran" (Dye Handbook) (published in
1970 and compiled by Society of Synthetic Organic Chemistry,
Japan). Examples of such dyes include azo dyes, metal complex salt
azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone
dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes,
methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal
thiolate complexes, oxonol dyes, diimonium dyes, aminium dyes and
croconium dyes.
[0117] Preferable dyes include e.g. the cyanine dyes described in
JP-A Nos. 58-125246, 59-84356, 59-202829, 60-78787 etc., the
methine dyes described in JP-A Nos. 58-173696, 58-181690, 58-194595
etc., the naphthoquinone dyes described in JP-A Nos. 58-112793,
58-224793, 59-48187, 59-73996, 60-52940, 60-63744 etc., the
squarylium dyes described in JP-A No. 58-112792 etc., and the
cyanine dyes described in GB Patent No. 434,875.
[0118] Further, the near infrared ray-absorbing sensitizer
described in U.S. Pat. No. 5,156,938 is also preferably used, and
also preferably used are the substituted aryl benzo (thio) pyrylium
salts described in U.S. Pat. No. 3,881,924, the trimethine
thiapyrylium salts described in JP-A No. 57-142645 (U.S. Pat. No.
4,327,169), the pyrylium type compounds described in JP-A Nos.
58-181051, 58-220143, 59-41363, 59-84248, 59-84249, 59-146063, and
59-146061, the cyanine dye described in JP-A No. 59-216146, the
pentamethine thiopyrylium salts described in U.S. Pat. No.
4,283,475, and the pyrylium compounds described in Japanese Patent
Application Publication (JP-B) Nos. 5-13514 and 5-19702.
[0119] Other preferable examples of dyes include the near infrared
ray-absorbing dyes of formulae (I) and (II) described in U.S. Pat.
No. 4,756,993.
[0120] Particularly preferable among these dyes are cyanine
pigments, phthalocyanine dyes, oxonol dyes, squarylium dyes,
pyrylium salts, thiopyrylium dyes and nickel thiolate complexes.
Further, the dyes represented by the general formulae (a) to (e)
below are preferable because of high light-heat conversion
efficiency, among which the cyanine dyes represented by the general
formula (a) below is most preferable because when used in the
polymerizable composition of the invention, the cyanine dye gives a
high polymerization activity and is economical and excellent in
stability. 13
[0121] In the general formula (a), X.sup.1 represents a hydrogen
atom, halogen atom, --NPh.sub.2, X.sup.2-L.sup.1 or the group shown
below. x.sup.2 represents an oxygen atom or sulfur atom, L.sup.1
represents a C.sub.1-12 hydrocarbon, an aromatic ring having a
heteroatom, and a C.sub.1-12 hydrocarbon group containing a
heteroatom. The heteroatom refers to N, S, O, halogen atom or Se.
14
[0122] R.sup.1 and R.sup.2 independently represent a C.sub.1-12
hydrocarbon group. For the storage stability of the recording layer
coating solution, each of R.sup.1 and R.sup.2 is preferably a
hydrocarbon group containing 2 or more carbon atoms, and more
preferably R.sup.1 and R.sup.2 are bound to each other to form a 5-
or 6-membered ring.
[0123] Ar.sup.1 and Ar.sup.2may be the same or different, and
represent an aromatic hydrocarbon group which may have a
substituent group. The aromatic hydrocarbon group is preferably a
benzene ring or naphthalene ring. The substituent group is
preferably a hydrocarbon group containing 12 or less carbon atoms,
or a halogen atom, or an alkoxy group containing 12 or less carbon
atoms. Y.sup.1 and Y.sup.2 may be the same or different, and
represent a sulfur atom or a dialkyl methylene group containing 12
or less carbon atoms. R.sup.3 and R.sup.4 may be the same or
different, and represent a hydrocarbon group containing 20 or less
carbon atoms, which may have a substituent group. The substituent
group is preferably an alkoxy group containing 12 or less carbon
atoms, or a carboxyl group or a sulfo group. R.sup.5, R.sup.6,
R.sup.7 and R.sup.8 may be the same or different, and represent a
hydrogen atom or a hydrocarbon group containing 12 or less carbon
atoms. Each of R.sup.5, R.sup.6, R.sup.7 and R.sup.8 is preferably
a hydrogen atom because the starting material is easily available.
Za.sup.- represents a counter anion. When any one of R.sup.1 to
R.sup.8 is substituted with a sulfo group, Za.sup.- is not
necessary. Because of the storage stability of the recording layer
coating solution, Za.sup.- is preferably a halogen ion, perchlorate
ion, tetrafluoroborate ion, hexafluorophosphate ion and sulfonate
ion, particularly preferably a perchlorate ion, hexafluorophosphate
ion and aryl sulfonate ion.
[0124] Examples of the cyanine dyes represented by the general
formula (a), which can be preferably used in the invention, include
those described in columns [0017] to [0019] in Japanese Patent
Application No. 11-310623, columns [0012] to [0038] in Japanese
Patent Application No. 2000-224031, and columns [0012] to [0023] in
Japanese Patent Application No. 2000-211147, in addition to those
exemplified below. 151617
[0125] In the general formula (b), L represents a methine chain
containing 7 or more conjugated carbon atoms, and the methine chain
may have substituent groups, and the substituent groups may be
bound to each other to form a ring structure. Zb.sup.+ represents a
counter cation. The counter cation is preferably ammonium,
iodonium, sulfonium, phosphonium, pyridinium and alkali metal
cations (Na.sup.+, K.sup.+, Li.sup.+). R.sup.9 to R.sup.14 and
R.sup.15 to R.sup.20 independently represent a substituent group
selected from a hydrogen atom, halogen atom, cyano group, alkyl
group, aryl group, alkenyl group, alkynyl group, carbonyl group,
thio group, sulfonyl group, sulfinyl group, oxy group and amino
group, or a substituent group in which two or three substituent
groups are combined with one another to form a ring structure. The
compound of the general formula (b) in which L represents a methine
chain containing 7 conjugated carbon atoms or all R.sup.9 to
R.sup.14 and R.sup.15 to R.sup.20 represent a hydrogen atom, are
preferable from the viewpoint of easy availability and effect.
[0126] Examples of the dyes represented by the general formula (b),
which can be used preferably in the invention, include those
exemplified below: 18
[0127] In the general formula (c), Y.sup.3 and Y.sup.4 each
represent an oxygen atom, sulfur atom, selenium atom or tellurium
atom; M represents a methine chain containing 5 or more conjugated
carbon atoms; R.sup.21 to R.sup.24 and R.sup.25 to R.sup.28 may be
the same or different and represent a hydrogen atom, halogen atom,
cyano group, alkyl group, aryl group, alkenyl group, alkynyl group,
carbonyl group, thio group, sulfonyl group, sulfinyl group, oxy
group and amino group; and Za.sup.- represents a counter anion and
has the same meaning as defined above for Za.sup.- in the general
formula (a).
[0128] Examples of the dyes represented by the general formula (c),
which can be used preferably in the invention, include those
exemplified below: 19
[0129] In the general formula (d), R.sup.29 to R.sup.31
independently represent a hydrogen atom, alkyl group or aryl group;
R.sup.33 and R.sup.34 independently represent an alkyl group, a
substituted oxy group or a halogen atom; n and m independently
represent an integer of 0 to 4; R.sup.29 and R.sup.30, or R.sup.31
and R.sup.32, may be bound to each other to form a ring, or
R.sup.29 and/or R.sup.30 may be bound to R.sup.33, or R.sup.31
and/or R.sup.32 may be bound to R.sup.34, to form a ring, and when
a plurality of R.sup.33 or R .sup.34 groups are present, R.sup.33
groups or R.sup.34 groups may be mutually bound to form a ring;
X.sup.2 and X.sup.3 independently represent a hydrogen atom, an
alkyl group or an aryl group, and at least one of X.sup.2 and
X.sup.3 represents a hydrogen atom or an alkyl group; Q is an
optionally substituted trimethine group or pentamethine group which
may form a ring structure with a divalent organic group; and
Zc.sup.- represents a counter anion and has the same meaning as
defined above for Za.sup.- in the general formula (a).
[0130] Examples of the dyes represented by the general formula (d),
which can be used preferably in the invention, include those
exemplified below: 2021
[0131] In the general formula (e), R.sup.35 to R.sup.50
independently represent a hydrogen atom, halogen atom, cyano group,
alkyl group, aryl group, alkenyl group, alkynyl group, hydroxyl
group, carbonyl group, thio group, sulfonyl group, sulfinyl group,
oxy group, amino group, and onium salt structure, all of which may
have a substituent group; and M represents two hydrogen atoms or a
metal atom, halometal group and oxymetal group, and the metal atom
contained therein includes the groups IA, IIA, IIIB and IVB atoms
in the periodic table, the transition metals in the first, second
and third periods, and lanthanoid elements, among which copper,
magnesium, iron, zinc, cobalt, aluminum, titanium and vanadium are
preferable.
[0132] Examples of the dyes represented by the general formula (e),
which can be used preferably in the invention, include those
exemplified below: 22
[0133] The pigment usable preferably as the light-heat converting
agent in the invention includes commercial pigments and those
described in Color Index (C. I.) Handbook, "Saishin Ganryo Binran"
(Newest Pigment Handbook) (published in 1977 and compiled by
Japanese Society of Pigment Technology), "Saishin Ganryho Oyo
Gijyutsu" (Newest Pigment Applied Technology) (published in 1986 by
CMC), and "Insatsu Inki Gijyutsu" (Printing Ink Technology)
(published in 1984 by CMC).
[0134] As the type of pigment, mention is made of black pigments,
yellow pigments, orange pigments, brown pigments, red pigments,
violet pigments, blue pigments, green pigments, fluorescent
pigments, metallic powder pigments, and other pigments such as
polymer-binding pigments. Specifically, it is possible to use
insoluble azo pigments, azo lake pigments, condensed azo pigments,
chelate azo pigments, phthalocyanine type pigments, anthraquinone
type pigments, perylene and perinone type pigments, thioindigo type
pigments, quinacridone type pigments, dioxazine type pigments,
isoindolinone type pigments, quinophthalone type pigments, dyed
lake pigments, azine pigments, nitroso pigments, nitro pigments,
natural pigments, fluorescent pigments, inorganic pigments, carbon
black etc. A preferable pigment among those described above is
carbon black.
[0135] For use, these pigments may or not may be subjected to
surface treatment. The method of surface treatment includes a
method of coating the surface thereof with resin or wax, a method
of allowing a surfactant to adhere thereto, and a method of bonding
a reactive material (e.g., a silane coupling agent, an epoxy
compound, a polyisocyanate etc.) onto the surface of the pigment.
These methods of surface treatment are described in "Kinzoku Sekken
No Seishitsu To Oyo" (Properties and Application of Metallic Soap)
(Saiwai Shobo), "Insatsu Inki Gijyutsu" (Printing Ink Technology)
(published in 1984 by CMC) and "Saishin Ganryho Oyo Gijyutsu"
(Newest Pigment Applied Technology) (published in 1986 by CMC).
[0136] The particle diameters of the pigments are in the range of
preferably 0.01 to 10 .mu.m, more preferably 0.05 to 1 .mu.m and
particularly preferably 0.1 to 1 .mu.m. Their particle diameters of
less than 0.01 .mu.m are not preferable in respect of the stability
of their dispersion in the image recording layer coating solution,
whereas their particle diameters of more than 10 .mu.m are not
preferable either in respect of the uniformity of the image
recording layer.
[0137] As the method of dispersing the pigments, any known
dispersion techniques used in production of inks or toners can be
used. As the dispersing machine, mention is made of a supersonic
dispersing device, sand mill, attritor, pearl mill, super mill,
ball mill, impeller, disperser, KD mill, colloid mill, dynatron,
triple roll mill, press kneader etc. These are described in detail
in "Saishin Ganryho Oyo Gijyutsu" (Newest Pigment Applied
Technology) (published in 1986 by CMC).
[0138] In the invention, these light-heat converting agents may be
used singly or in combination thereof, but from the viewpoint of
sensitivity, the light-heat converting agent is preferably the
pigment shown in the general formula (a), most preferably the
cyanine pigment having a diaryl amino group.
[0139] The light-heat converting agent is added preferably in an
amount of 0.1 to 20% by weight based on the total solids content of
the heat-sensitive composition. If the amount of the light-heat
converting agent is lower than this range, the sensitivity of
characteristic change by light exposure tends to be lowered thus
failing to achieve sufficient photosensitivity, while if its amount
is higher than this range, the uniformity and strength of the
resultant film tend to be lowered, so both the cases are not
preferable.
[0140] The light-heat converting agent, along with other
components, may be added to the same layer or to a separately
provided layer such that in the resultant negative image forming
material, the optical density of the recording layer at the
absorption maximum at a wavelength in the range of 760 to 1200 nm
is preferably in the range of 0.1 to 3.0. If the optical density is
outside of this range, the sensitivity tends to be lowered. Because
the optical density is determined by both the amount of the
light-heat converting agent added and the thickness of the
recording layer, the predetermined optical density can be achieved
by regulating conditions for the two factors. The optical density
of the recording layer can be measured in a usual manner. In this
measurement, there is a method in which a recording layer which
after drying, has suitably determined thickness in a range
necessary as a planographic printing plate is formed on e.g. a
transparent or white support and then measured by a transmission
optical densitometer, or the recording layer is formed on a
reflective support such as aluminum and then measured for its
reflective density.
[0141] (C) Radical Initiator
[0142] The compound generating radicals with heat-mode light
exposure (radical initiator) is used in combination with (B)
light-heat converting agent described above, and refers to a
compound generating radicals by the energy of light and/or heat
upon irradiation with light (from e.g. an infrared laser) at a
wavelength that can be absorbed by the light-heat converting agent,
thus initiating and promoting polymerization of (A) polymer
compound which is soluble in an aqueous alkaline solution, has at
least one carbon-carbon double bond in a side chain thereof and has
a glass transition temperature of 100.degree. C. or more and (D)
optionally used radical-polymerizable compound having a
polymerizable unsaturated group described later. The "heat-mode
light exposure" follows the definition described above in the
invention.
[0143] The radical initiator used can be selected from known
photopolymerization initiators and heat polymerization initiators,
and examples thereof include onium salts, triazine compounds having
a trihalomethyl group, peroxides, azo-type polymerization
initiators, azide compounds and quinone diazide, among which the
onium salts are highly sensitive and preferable.
[0144] The radical-generating compound that can be used preferably
in the invention includes onium salts, which are specifically
iodonium salts, diazonium salts or sulfonium salts. The onium salt
functions not as an acid generator but also as a radical
polymerization initiator when used in combination with a
radical-polymerizable compound described later. The onium salts
used preferably in the invention are those onium salts represented
by the general formulae (III) to (V): 23
[0145] In the formula (III), Ar.sup.11 and Ar.sup.12 independently
represent an aryl group containing 20 or less carbon atoms, which
may have a substituent group. When this aryl group has a
substituent group, the substituent group is preferably a halogen
atom, a nitro group, an alkyl group containing 12 or less carbon
atoms, an alkoxy group containing 12 or less carbon atoms, or an
aryloxy group containing 12 or less carbon atoms. Za.sup.11-
represents a counterion selected from the group consisting of a
halogen ion, perchlorate ion, carboxylate ion, tetrafluoroborate
ion, hexafluorophosphate ion and sulfonate ion, preferably a
perchlorate ion, hexafluorophosphate ion and aryl sulfonate
ion.
[0146] In formula (IV), Ar.sup.21 represents an aryl group
containing 20 or less carbon atoms, which may have a substituent
group. The substituent is preferably a halogen atom, a nitro group,
an alkyl group containing 12 or less carbon atoms, an alkoxy group
containing 12 or less carbon atoms, an aryloxy group containing 12
or less carbon atoms, an alkylamino group containing 12 or less
carbon atoms, a dialkyl amino group containing 12 or less carbon
atoms, an aryl amino group containing 12 or less carbon atoms, or a
diaryl amino group containing 12 or less carbon atoms. Z.sup.21-
represents a counterion having the same meaning as defined for
Z.sup.11-.
[0147] In formula (V), R.sup.31, R.sup.32 and R.sup.33 may be the
same or different, and represent a hydrocarbon group containing 20
or less carbon atoms, which may have a substituent group. The
substituent is preferably a halogen atom, a nitro group, an alkyl
group containing 12 or less carbon atoms, an alkoxy group
containing 12 or less carbon atoms or an aryloxy group containing
12 or less carbon atoms. z.sup.31 represents a counterion having
the same meaning as defined for Z.sup.11-.
[0148] Examples of the onium salts that can be used preferably in
the invention include the applicant's proposed ones described in
columns [0030] to [0033] in Japanese Patent Application No
11-310623 and those in columns [0015] to [0046] in Japanese Patent
Application No. 2000-160323.
[0149] The onium salt used in the invention has a maximum
absorption wavelength of preferably 400 nm or less, more preferably
360 nm or less. By using the onium salt having its absorption
wavelength in the UV range, the planographic printing plate
precursor can be handled under an incandescent lamp.
[0150] These onium salts can be added to the recording layer
coating solution in a ratio of 0.1 to 50% by weight, preferably 0.5
to 30% by weight, particularly preferably 1 to 20% by weight to the
solids content of the recording layer coating solution. If the
amount of the salts is less than 0.1% by weight, the sensitivity is
lowered, while if the amount is greater than 50% by weight, smuts
occur on the non-image portion during printing. These onium salts
may be used alone or in combination thereof. Further, these onium
salts together with other components may be added to the same layer
or another layer that is separately arranged.
[0151] (D) Radical-Polymerizable Compound
[0152] In the image recording material of the invention, a
radical-polymerizable compound can be used in combination in order
to improve sensitivity and image formability. The
radical-polymerizable compound that can be used in combination is a
radical-polymerizable compound having at least one ethylenically
unsaturated double bond, and is selected from those compounds
having at least one (preferably two or more) terminal ethylenically
unsaturated bond. Such a compound group is used widely in this
industrial field, and in the invention, these compounds can be used
without any particular limitation. These compounds are in chemical
forms such as monomers, prepolymers, that is, dimers, trimers and
oligomers, as well as mixtures and copolymers thereof.
[0153] Examples of such monomers and copolymers include unsaturated
carboxylic acids (e.g., acrylic acid, methacrylic acid, itaconic
acid, crotonic acid, isocrotonic acid, maleic acid etc.) and esters
and amides thereof, and preferably used are esters between
unsaturated carboxylic acids and aliphatic polyvalent alcohols and
amides between unsaturated carboxylic acids and aliphatic
polyvalent amines. Further, dehydration condensation reaction
products of unsaturated carboxylates or amides having nucleophilic
substituent groups such as hydroxyl group, amino group, mercapto
group and so on, with monofunctional or multifunctional isocyanates
or epoxy compound can be preferably used. Further,
addition-reaction products of unsaturated carboxylates or amides
having nucleophilic substituent groups such as hydroxyl group,
amino group, mercapto group and so on, with monofunctional or
multifunctional carboxylic acids can be preferably used.
[0154] Further, addition-reaction products of unsaturated
carboxylates or amides having electrophilic substituent groups such
as isocyanate group, epoxy group and so on, with monofunctional or
multifunctional alcohols, amines or thiols can be preferably used.
Further, substitution-reaction products of unsaturated carboxylates
or amides having eliminating substituent groups such as halogen
group, tosyloxy group and so on, with monofunctional or
multifunctional alcohols, amines or thiols can be preferably used.
Further, a group of those compounds in which the above-described
carboxylic acids have been respectively replaced by unsaturated
phosphonic acids, styrene and so on, can also be preferably
used.
[0155] Among the radical-polymerizable compounds as esters between
aliphatic polyvalent alcohols and unsaturated carboxylic acids, the
acrylates include ethylene glycol diacrylate, triethylene glycol
diacrylate, 1,3-butane diol diacrylate, tetramethylene glycol
diacrylate, propylene glycol diacrylate, neopentyl glycol
diacrylate, trimethylol propane triacrylate, trimethylol propane
tri(acryloyloxy propyl) ether, trimethylol ethane triacrylate,
hexane diol diacrylate, 1,4-cyclohexane diol diacrylate,
tetraethylene glycol diacrylate, pentaerythritol diacrylate,
pentaerythritol triacrylate, pentaerythritol tetracrylate,
dipentaerythritol diacrylate, dipentaerythritol hexacrylate,
sorbitol triacrylate, sorbitol tetracrylate, sorbitol pentacrylate,
sorbitol hexacrylate, tri (acryloyloxy ethyl) isocyanurate,
polyester acrylate oligomers etc.
[0156] The methacrylates include tetramethylene glycol
dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol
dimethacrylate, trimethylol propane trimethacrylate, trimethylol
ethane trimethacrylate, ethylene glycol dimethacrylate, 1,3-butane
diol dimethacrylate, hexane diol dimethacrylate, pentaerythritol
dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol
tetramethacrylate, dipentaerythritol dimethacrylate,
dipentaerythritol hexamethacrylate, sorbitol trimethacrylate,
sorbitol tetramethacrylate, bis[p-(3-methacryloxy-2-hydr-
oxypropyl) phenyl] dimethyl methane, bis[p-(methacryloxy ethoxy)
phenyl] dimethyl methane etc.
[0157] The itaconates include ethylene glycol diitaconate,
propylene glycol diitaconate, 1,3-butane diol diitaconate,
1,4-butane diol diitaconate, tetramethylene glycol diitaconate,
pentaerythritol diitaconate, sorbitol tetraitaconate etc.
[0158] The crotonates include ethylene glycol dicrotonate,
tetramethylene glycol dicrotonate, pentaerythritol dicrotonate,
sorbitol tetracrotonate etc.
[0159] The isocrotonates include ethylene glycol diisocrotonate,
pentaerythritol diisocrotonate, sorbitol tetraisocrotonate etc.
[0160] The maleates include ethylene glycol dimaleate, triethylene
glycol dimaleate, pentaerythritol dimaleate, sorbitol tetramaleate
etc.
[0161] Other esters, which can also be preferably used, include
e.g. the aliphatic alcohol-based esters described in JP-B Nos.
46-27926 and 51-47334 and JP-A No. 57-196231, those having an
aromatic skeleton described in JP-A Nos. 59-5240, 59-5241 and
2-226149, and those having an amino group described in JP-A No.
1-165613.
[0162] As the monomers, the amides between aliphatic polyvalent
amines and unsaturated carboxylic acids include e.g. methylene
bis-acrylamide, methylene bis-methacrylamide, 1,6-hexamethylene
bis-acrylamide, 1,6-hexamethylene bis-methacrylamide, diethylene
triamine trisacrylamide, xylylene bisacrylamide, xylylene
bismethacrylamide etc.
[0163] Preferable examples of other amide type monomers include
those having a cyclohexylene structure described in JP-B No.
54-21726.
[0164] Further, urethane type addition-polymerizable compounds
produced by addition reaction between isocyanates and hydroxyl
groups are also preferable, and specific examples thereof include
vinyl urethane compounds containing two or more polymerizable vinyl
groups in one molecule, which are prepared by adding vinyl monomers
containing a hydroxyl group shown in formula (VI) below to
polyisocyanates compound having two or more isocyanate groups in
one molecule as described in JP-B No. 48-41708.
CH.sub.2.dbd.C(R.sup.34)COOCH.sub.2CH(R.sup.35)OH (VI)
[0165] In the formula (IV), R.sup.34 and R.sup.35 independently
represent a hydrogen atom or a methyl group.
[0166] Further, the urethane acrylates described in JP-A No.
51-37193, JP-B Nos. 2-32293 and 2-16765, and the urethane compounds
having an ethylene oxide-type skeleton described in JP-B Nos.
58-49860, 56-17654, 62-39417 and 62-39418 are also preferable.
[0167] Also, the radical-polymerizable compounds having an amino
structure or sulfide structure in the molecule as described in JP-A
Nos. 63-277653, 63-260909 and 1-105238 may be used.
[0168] As other examples, the multifunctional acrylates and
methacrylates such as polyacrylates and epoxy acrylates obtained by
reacting epoxy resin with (meth)acrylic acid described in JP-A No.
48-64183, JP-B Nos. 49-43191 and 52-30490 can be mentioned.
Further, the specific unsaturated compounds described in JP-B Nos.
46-43946, 1-40337 and 1-40336, and the vinyl phosphonic acid-type
compounds described in JP-A No. 2-25493 can also be mentioned. In
some cases, the structure containing a perfluoroalkyl group
described in JP-A No. 61-22048 is preferably used. Further, the
photo-curable monomers and oligomers described in the Journal of
Japanese Adhesive Society, vol. 20, No. 7, pp. 300-308 (1984) can
also be used.
[0169] The radical-polymerizable compounds may be used singly or in
combination thereof. How these radical-polymerizable compounds are
used, that is, what structure is used, whether they are used singly
or in combination, and in which amount they are used, can be
arbitrarily determined depending on the performance and design of
the final recording material.
[0170] A higher compounding ratio of the radical-polymerizable
compound in the image recording material is advantageous to
sensitivity, but when the ratio is too high, there arise occurrence
of undesirable phase separation, a problem such as adhesion of the
image recording layer in the production process (for example,
production failure attributable to the transfer and adhesion of the
components in the recording layer) and a problem such as
precipitation from the developing solution. From these viewpoints,
the compounding ratio of the radical-polymerizable compound in many
cases is preferably 5 to 80% by weight, preferably 20 to 75% by
weight, in the components in the composition.
[0171] In the invention, when the specific alkali-soluble polymer
(A) is used in combination with the radical-polymerizable compound
(D), the component (A):component (D) ratio by weight is in the
range of 1:0.05 to 1:3, preferably in the range of 1:0.1 to 1:2,
more preferably in the range of 1:0.3 to 1:1.5.
[0172] From the viewpoints of the inhibition of polymerization by
oxygen, resolution, hiding power, a change in reflectance, surface
adhesiveness etc., a suitable structure, compounding and amount
thereof can be arbitrarily selected in the method of using the
radical-polymerizable compound, and further a layer structure and a
coating method such as undercoating and overcoating can also be
carried out if necessary.
[0173] Other Components
[0174] In the image recording material of the invention, various
compounds other than those described above can be further added if
necessary. For example, a dye having considerable absorption in the
visible-light range can be used as a coloring agent for images.
Specifically, mention can be made of Oil Yellow #101, Oil Yellow
#103, Oil Pink #312, Oil Green BC, Oil Blue BOS, Oil Blue #603, Oil
Black BY, Oil Black BS, Oil Black T-505 (which are available from
Orient Chemical Industries, Ltd.), Victoria Pure Blue, Crystal
Violet (CI42555), Methyl Violet (CI42535), Ethyl Violet, Rhodamine
B (CI145170B), Malachite Green (CI42000), Methylene Blue (CI52015)
etc. Further, the dyes described in JP-A No.62-293247 are
particularly preferable. Further, pigments such as phthalocyanine
type pigments, azo type pigments, carbon black and titanium oxide
can also be preferably used.
[0175] These dyes are preferably added to facilitate distinction of
the image portion from the non-image portion. The amount of the dye
is 0.01 to 10% by weight based on the total solids content of the
recording layer coating solution.
[0176] In the invention, a small amount of a heat-polymerizable
inhibitor is desirably added to inhibit undesired heat
polymerization of the radical polymerizable compound in the image
recording material during preparation or storage. Examples of
suitable heat-polymerization inhibitors include hydroquinone,
p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butyl catechol,
benzoquinone, 4,4'-thiobis (3-methyl-6-t-butyl phenol),
2,2'-methylene bis(4-methyl-6-t-butyl phenol), N-nitroso-N-phenyl
hydroxylamine aluminum salt etc. The amount of the
heat-polymerization inhibitor added is preferably about 0.01 to
about 5% by weight relative to the total weight of the composition.
To prevent the inhibition of polymerization by oxygen, a higher
fatty acid derivative such as behenic acid or behenic amide may be
added if necessary so that it is allowed to be locally present on
the surface of the recording layer in the drying step after
application. The amount of the higher fatty acid derivative added
is preferably about 0.1 to about 10% by weight relative to the
entire composition.
[0177] The image forming material in the invention is used for
forming an image recording layer mainly in a planographic printing
plate precursor, and for improving the stability of the image
recording layer to development treatment under development
conditions, nonionic surfactants such as those described in JP-A
Nos. 62-251740 and 3-208514 and amphoteric surfactants such as
those described in JP-A Nos. 59-121044 and 4-13149 can be
added.
[0178] Specific examples of the nonionic surfactants include
sorbitan tristearate, sorbitan monopalmitate, sorbitan trioleate,
stearate monoglyceride, polyoxyethylene nonyl phenyl ether etc.
[0179] Specific examples of the amphoteric surfactants include
alkyl di (aminoethyl) glycine, alkyl polyaminoethyl glycine
hydrochloride, 2-alkyl-N-carboxyethyl-N-hydroxyethyl imidazolium
betaine and N-tetradecyl-N,N-betaine type surfactants (e.g. trade
name: Amogen K, Dai-Ichi Kogyo Co., Ltd.).
[0180] The amount of the nonionic surfactants and amphoteric
surfactants in the recording layer coating solution is preferably
0.05 to 15% by weight, more preferably 0.1 to 5% by weight.
[0181] Further, a plasticizer is added if necessary to the
recording layer coating solution in order to confer e.g.
flexibility on the coating. For example, polyethylene glycol,
tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl
phthalate, dioctyl phthalate, tricresyl phosphate, tributyl
phosphate, trioctyl phosphate and tetrahydrofurfuryl oleate are
used.
[0182] When the image forming material of the invention is used to
produce a planographic printing plate precursor, the constituent
components of the image forming material, together with components
necessary for the coating solution, are dissolved in a solvent and
then applied onto a suitable substrate. The solvent used here
includes, but is not limited to, ethylene dichloride,
cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol,
ethylene glycol monomethyl ether, 1-methoxy-2-propanol,
2-methoxyethyl acetate, 1-methoxy-2-propyl acetate,
dimethoxyethane, methyl lactate, ethyl lactate, N,N-dimethyl
acetamide, N,N-dimethyl formamide, tetramethyl urea, N-methyl
pyrrolidone, dimethyl sulfoxide, sulfolane, .gamma.-butyl lactone,
toluene, water etc. These solvents are used singly or as a mixture
thereof. The concentration of the above components (total solids
content including additives) in the solvent is preferably 1 to 50%
by weight.
[0183] The amount of the recording layer (solids content) coated
and dried on the substrate is varied depending on the intended use,
but generally, the amount thereof for the planographic printing
plate precursor is preferably 0.5 to 5.0 g/m.sup.2. As its coating
is decreased, the apparent sensitivity is improved, but the film
characteristics of the image recording layer are lowered.
[0184] For coating, various methods can be used, and for example,
bar coating, rotational coating, spray coating, curtain coating,
dip coating, air knife coating, blade coating and roll coating can
be mentioned.
[0185] Surfactants for improving coating properties, for example
the fluorine type surfactants described in JP-A No. 62-170950, can
be added to the recording layer coating solution in the invention.
The amount of the surfactant added is preferably 0.01 to 1% by
weight, more preferably 0.05 to 0.5% by weight, relative to the
solids content of the entire recording layer.
[0186] In this manner, with respect to the softening temperature of
an image recording layer formed on a support member, that is, a
photosensitive layer, it is preferably set to not less than
60.degree. C. If the temperature is below 60.degree. C., the
storage stability is lowered. In the case when a low-molecular
component, such as a radical polymerizable compound, exists as a
photosensitive layer composition, the softening temperature of the
photosensitive layer drops; however, the application of a binder
having a glass transition temperature of not less than 80.degree.
C. is effective so as to maintain the softening temperature at not
less than 60.degree. C. Here, the softening temperature of the
photosensitive layer is measured by using a differential scanning
calorimeter (DSC) or a visco-elasticity measuring meter.
[0187] The image recording material of the invention is used mainly
as a recording layer in a planographic printing plate precursor.
The planographic printing plate precursor has at least a substrate,
a recording layer and if necessary a protective layer. The
substrate and protective layer as the constituent elements of the
planographic printing plate precursor are described below.
[0188] Substrate
[0189] The substrate used in forming a planographic printing plate
precursor from the image forming material of the invention is not
particularly limited insofar as it is a dimensionally stable plate,
and examples thereof include a paper, a paper with plastics (e.g.,
polyethylene, polypropylene, polystyrene etc.) laminated thereon, a
metal plate (e.g., aluminum, zinc, copper etc.), plastic film
(e.g., diacetate cellulose, triacetate cellulose, propionate
cellulose, butyrate cellulose, acetate butyrate cellulose, nitrate
cellulose, polyethylene terephthalate, polyethylene, polystyrene,
polypropylene, polycarbonate, polyvinyl acetal etc.), etc. These
may be single-component sheets such as resinous film and metal
plate, or laminates consisting of two or more materials laminated
therein, such as a paper or plastic film having the above-described
metal laminated or vapor-deposited thereon or a laminate sheet
consisting of different plastic films, etc.
[0190] The substrate is preferably a polyester film or an aluminum
plate, among which the aluminum plate is excellent in dimensional
stability and relatively inexpensive and is thus particularly
preferable. The aluminum plate is preferably a pure aluminum plate
or an alloy plate based on aluminum containing a trace of different
elements, and may be a plastic film having aluminum laminated or
vapor-deposited thereon. The different elements contained in the
aluminum alloy include silicon, iron, manganese, copper, magnesium,
chromium, zinc, bismuth, nickel, titanium etc. The content of the
different elements in the alloy is up to 10% by weight.
Particularly preferable aluminum in the invention is pure aluminum,
but because production of absolutely pure aluminum is difficult in
refining techniques, aluminum may contain a trace of different
elements. The composition of the aluminum plate thus used in the
invention is not limited, and any aluminum plates made of a known
and conventionally used aluminum material can be used if
necessary.
[0191] The thickness of the aluminum plate is about 0.1 to 0.6 mm,
preferably 0.15 to 0.4 mm and most preferably 0.2 to 0.3 mm.
[0192] Before the surface of the aluminum plate is roughened,
degreasing treatment with e.g. a surfactant, an organic solvent or
an aqueous alkali solution is conducted if necessary for removal of
rolling oil on the surface thereof.
[0193] The treatment of roughening the surface of the aluminum
plate is conducted in various methods such as a method of
mechanical surface roughening, a method of surface roughening by
electrochemical dissolution of the surface and a method of
chemically and selectively dissolving the surface. The mechanical
method can make use of known techniques such as ball grinding,
brush grinding, blast grinding and buff grinding. The
electrochemical roughening method includes a method of roughening
the surface in a hydrochloric acid or nitric acid electrolyte by
use of alternating current or direct current. Further, a
combination of both the methods can also be utilized as disclosed
in JP-A No. 54-63902.
[0194] After the aluminum plate thus surface-roughened is subjected
if necessary to alkali etching treatment and neutralization
treatment, the plate can be subjected to anodizing treatment in
order to improve the water retention and abrasion resistance of the
surface. The electrolyte for use in the anodizing treatment of the
aluminum plate can be selected from various electrolytes for
forming a porous oxide film, and generally sulfuric acid,
phosphoric acid, oxalic acid, chromic acid or a mixed acid thereof
is used. The concentration of the electrolyte is determined
suitably depending on the type of the electrolyte.
[0195] The conditions for the anodizing treatment are varied
depending on the electrolyte used and can thus not be generalized,
but it is usually preferable that the concentration of the
electrolyte is 1 to 80% by weight, the liquid temperature is 5 to
70.degree. C., the current density is 5 to 60 A/dm.sup.2, the
voltage is 1 to 100 V, and the electrolysis time is 10 seconds to 5
minutes.
[0196] The amount of the anodized film is preferably not less 1.0
g/m.sup.2, more preferably in the range of 2.0 to 6.0 g/m.sup.2. If
the anodized film is less than 1.0 g/m.sup.2, the printing
resistance becomes insufficient and the non-image portion on the
planographic printing plate is easily marred to have the so-called
"mar staining" which is caused by ink adhering to the mar upon
printing.
[0197] The printing surface of the substrate in the planographic
printing plate is subjected to such anodizing treatment, but
because of the line of electric force sent to the back thereof,
0.01 to 3g/m.sup.2 anodized film is generally formed on the back as
well.
[0198] The treatment for rendering the surface of the substrate
hydrophilic, which is conducted after the anodizing treatment
described above, can make use of a treatment method known in the
art. Such hydrophilicity-conferring treatment includes the alkali
metal silicate (e.g., an aqueous solution of sodium silicate)
method disclosed in U.S. Pat. Nos. 2,714,066, 3,181,461, 3,280,734
and 3,902,734. In this method, the substrate is dipped or
electrolyzed in an aqueous solution of sodium silicate. Besides,
the method of treatment with potassium fluorozirconate as disclosed
in JP-B No. 36-22063 and the method of treatment with polyvinyl
phosphonic acid as disclosed in U.S. Pat. Nos. 3,276,868,
4,153,461, and 4,689,272 are used.
[0199] Among these treatments, particularly preferable
hydrophilicity-conferring treatment in the invention is the
treatment with silicates. The treatment with silicates is described
below.
[0200] The anodized film on the aluminum plate which was subjected
to the treatment described above is dipped for example at 15 to
80.degree. C. for 0.5 to 120 seconds in an aqueous solution of an
alkali metal silicate at a concentration of 0.1 to 30% by weight,
preferably 0.5 to 10% by weight, at a pH 10 to 13 at 25.degree. C.
If the pH value of the aqueous alkali metal silicate solution is 10
or less, the solution is gelled, while if the pH value is higher
than 13.0, the anodized film is dissolved. As the alkali metal
silicate used in the invention, sodium silicate, potassium
silicate, lithium silicate etc. are used. The hydroxide used for
raising the pH value of the aqueous alkali metal silicate solution
includes sodium hydroxide, potassium hydroxide, lithium hydroxide
etc. Alkaline earth metal salts or the group IVB metal salts may be
incorporated into the treating solution described above. The
alkaline earth metals include nitrates such as calcium nitrate,
strontium nitrate, magnesium nitrate and barium nitrate, and
water-soluble salts such as nitrate, hydrochloride, phosphate,
acetate, oxalate and borate. The group IVB metal salts include
titanium tetrachloride, titanium trichloride, titanium potassium
fluoride, titanium potassium oxalate, titanium sulfate, titanium
tetraiodide, zirconium chloride oxide, zirconium dioxide, zirconium
oxychloride, zirconium tetrachloride etc. The alkaline earth metal
salts or the group IVB metal salts can be used singly or in
combination thereof. The amount of these metal salts is preferably
in the range of 0.01 to 10% by weight, more preferably 0.05 to 5.0%
by weight.
[0201] Because the hydrophilicity of the surface of the aluminum
plate is further improved by silicate treatment, the ink hardly
adheres to the non-image portion during printing, and the stain
resistance is improved.
[0202] The substrate is provided if necessary with a back coat on
the back thereof. The back coat is preferably a coating layer
consisting of metal oxides obtained by hydrolysis and
polycondensation of the organic polymer compounds described in JP-A
No. 5-45885 and the organic or inorganic metal compounds described
in JP-A No. 6-35174.
[0203] Among these coating layers, coating layers of metal oxides
obtained from alkoxy silicon compounds such as Si(OCH.sub.3).sub.4,
Si(OC.sub.2H.sub.5).sub.4, Si(OC.sub.3H.sub.7).sub.4 and
Si(OC.sub.4H.sub.9).sub.4 are particularly preferable because these
layers are excellent in development resistance and these starting
materials are available easily and inexpensively.
[0204] Protective Layer
[0205] When used in a planographic printing plate precursor, the
image recording material of the invention is exposed to light
usually in the air, so preferably the image recording layer
containing the photo-polymerizable composition is provided thereon
with a protective layer, in which the desired characteristics of
the protective layer are low permeability of low-molecular
compounds such as oxygen, good permeability of light used in light
exposure, excellent adhesion to the recording layer, and high
removability in the development step after light exposure, and the
materials used in the protective layer are preferably water-soluble
polymer compounds relatively excellent in crystallinity, such as
polyvinyl alcohol, polyvinyl pyrrolidone, acidic celluloses,
gelatin, gum arabic and polyacrylic acid.
[0206] In the image recording material of the invention, the
specific polyurethane resin having low oxygen dissolved in its
coating and a high ability to shield the image recording layer
against oxygen in the outside is used as the film-forming resin,
thus advantageously preventing the deterioration of image
formability caused by the inhibition of polymerization by oxygen,
so the protective layer may not necessarily be arranged, but for
the purpose of further improving the ability to shield it against
oxygen in the outside thus improving image formability particularly
image strength, the protective layer may be arranged.
[0207] Printing by the Planographic Printing Plate Precursor
[0208] A planographic printing plate precursor prepared by using
the imager-recording material of the invention as the recording
layer can be used in recording by an infrared laser Further,
thermal recording by a UV lamp or thermal head is also feasible. In
the invention, the image thereon is exposed to light preferably by
a solid laser and a semiconductor laser emitting infrared rays of
wavelengths of from 760 nm to 1200 nm.
[0209] After exposed to light by the infrared laser, the image
forming material of the invention is developed preferably with
water or an aqueous alkaline solution.
[0210] When the aqueous alkaline solution is used as a developing
solution, the developing solution and its supplementary solution
for the image recording material of the invention may be an aqueous
alkali solution known in the art. For example, mention is made of
inorganic alkali salts such as sodium silicate, potassium silicate,
tribasic sodium phosphate, tribasic potassium phosphate, tribasic
ammonium phosphate, dibasic sodium phosphate, dibasic potassium
phosphate, dibasic ammonium phosphate, sodium carbonate, potassium
carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium
hydrogen carbonate, ammonium hydrogen carbonate, sodium borate,
potassium borate, ammonium borate, sodium hydroxide, ammonium
hydroxide, potassium hydroxide and lithium hydroxide. Further, use
is made of organic alkali agents such as monomethylamine,
dimethylamine, trimethylamine, monoethylamine, diethylamine,
triethylamine, monoisopropylamine, diisopropylamine,
triisopropylamine, n-butylamine, monoethanolamine, diethanolamine,
triethanolamine, monoisopropanolamine, diisopropanolamine, ethylene
imine, ethylene diamine, and pyridine.
[0211] These alkali agents are used singly or in combination
thereof.
[0212] It is also known that when the development is conducted in
an automatic developer, an aqueous solution of higher alkali
strength (supplementary solution) than in the developing solution
is added to the developing solution, whereby a large number of
planographic printing plate precursors can be treated without
exchanging the developing solution with the fresh one for a
prolonged period of time in the development tank. This
supplementing system can also be preferably applied to the
invention.
[0213] For promoting and suppressing developing performance, for
dispersing development residues and for improving the affinity of
the image portion on the printing plate for ink, various
surfactants and organic solvents can be added if necessary to the
developing solution and the supplementary solution. Preferable
surfactants include anionic, cationic, nonionic and amphoteric
surfactants. A preferable organic solvent is benzyl alcohol.
Addition of polyethylene glycol or derivatives thereof or
polypropylene glycol or derivatives thereof is also preferable.
Further, non-reducing sugars such as arabitol, sorbitol and
mannitol can also be added.
[0214] Reducing agents such as hydroquinone, resorcin, or inorganic
salts such as sodium and potassium sulfite or hydrogensulfite,
organic carboxylic acids, defoaming agents and hard-water
softeners, can also be added if necessary to the developing
solution and the supplementary solution.
[0215] The printing plate which was subjected to development
treatment with the developing solution and the supplementary
solution described above is post-treated with washing water, a
surfactant-containing rinse, and an insensitizing greasing solution
containing gum arabic and starch derivatives. When the image
recording material of the invention is used as a printing plate
material, these treatments can be used in combination as
post-treatment.
[0216] In the industrial fields of plate making and printing, an
automatic developing machine for printing plate is used widely in
recent years for rationalization and standardization for the
operation of plate making. This automatic developing machine
consists generally of a developing part, a post-treatment part, a
device for transferring a printing plate, each treating solution
bath and a spraying device, and while a printing plate after light
exposure is transferred horizontally, each treating solution drawn
by a pump is sprayed for development onto the printing plate
through a spray nozzle. Recently, a method of dipping-treating a
printing plate in a treating solution bath filled with a treating
solution while transferring it by use of guide rolls in the
solution is also known. Such automatic treatment can be carried out
by supplementing each treatment solution with a supplementary
solution, depending on throughput, operation time etc. Further, the
supplementary solution can be automatically fed while the
electrical conductance is sensed with a sensor.
[0217] The so-called "throwaway" treatment system of treatment with
a substantially virgin treating solution can also be applied.
[0218] The planographic printing plate thus obtained is coated with
an insensitizing greasing gum if necessary and then subjected to
printing, but if the planographic printing plate with higher
printing resistance is desired, it is subjected to burning
treatment.
[0219] When the planographic printing plate is subjected to
burning, the plate before burning is treated preferably with those
surface-adjusting solutions described in JP-B Nos. 61-2518,
55-28062, JP-A Nos. 62-31859 and 61-159655.
[0220] For this treatment, use is made of a method of applying a
sponge or adsorbent cotton impregnated with the surface-adjusting
solution onto the planographic printing plate, or dipping the
printing plate in a vat filled with the surface-adjusting solution,
or coating by an automatic coater. Further, better results are
given by applying the surface-adjusting solution uniformly by an
squeezer or with squeeze rollers.
[0221] Generally, the amount of the surface-adjusting solution
applied is preferably 0.03 to 0.8 g/m.sup.2 (dry weight).
[0222] The planographic printing plate coated with the
surface-adjusting solution is dried if necessary and then heated at
high temperatures by a burning processor (e.g. a burning processor
BP-1300 from Fuji Photo Film Co., Ltd.). In this case, the heating
temperature and time are varied depending the type of components
forming the image, but are preferably 180 to 300.degree. C. and 1
to 20 minutes.
[0223] After burning treatment, the planographic printing plate can
be subjected to conventional treatments such as washing with water
and gumming drawing if necessary, but if a surface-adjusting
solution containing water-soluble polymers etc. is used, the
so-called insensitizing greasing treatment such as gumming drawing
can be omitted.
[0224] The planographic printing plate obtained from the image
recording material of the invention is loaded onto an offset
printing machine etc. and used for printing on multiple papers.
EXAMPLES
[0225] Hereinafter, the present invention is described by reference
to Synthesis Examples, Examples and Comparative Examples, which
however are not intended to limit the invention.
Synthesis Examples
Synthesis Example 1
Specific Alkali-Soluble Polymer Compound 1
[0226] 60 ml of N,N-dimethylacetamide was placed in a 500-ml
three-necked flask equipped with a condenser and a stirrer, and
then heated at 70.degree. C. 60 ml solution of 50 g of 4 -carboxyl
styrene and 2.49 g of V-65 (Wako Pure Chemical Industries, Ltd.) in
N,N-dimethyl acetamide was added dropwise over 2.5 hours in a
nitrogen stream. Further, the mixture was reacted at 70.degree. C.
for 2 hours. The reaction mixture was diluted with 120 ml of
N,N-dimethylacetamide and cooled to room temperature, and 34 g of
triethylamine was added dropwise via a dropping funnel to the
reaction mixture under stirring. After this addition was finished,
47 g of 3-bromopropyl methacrylate was added dropwise via a
dropping funnel to the reaction solution under stirring, and the
mixture was reacted for 8 hours.
[0227] After the reaction mixture was cooled to 0.degree. C., 5 M
HCl was added dropwise thereto under stirring until the pH value of
the reaction mixture was reduced to 6 or less. The reaction
solution was poured into 5 L of water to precipitate a polymer.
This product was collected by filtration, washed with water and
dried to give a polymer compound 1.
[0228] By its NMR spectrum, it was confirmed that 70% of the
carboxyl groups of the polymer had been converted into
3-methacryloyloxy propyl ester. The glass transition temperature as
determined by DSC was 105.degree. C., and the weight average
molecular weight as determined by gel permeation chromatography
(GPC) using polystyrene as the standard was 90, 000.
Synthesis Example 2
Specific Alkali-Soluble Polymer Compound 2
[0229] 150 ml of N,N-dimethylacetamide was placed in a 1000-ml
three-necked flask equipped with a condenser and a stirrer, and
then heated at 70.degree. C. 150 ml solution of 74 g of 4-carboxy
styrene, 52 g of styrene and 2.46 g of V-65 (Wako Pure Chemical
Industries, Ltd.) in N,N-dimethyl acetamide was added dropwise over
2.5 hours in a nitrogen stream. Further, the mixture was reacted at
70.degree. C. for 2 hours. The reaction mixture was diluted with
150 ml of N,N-dimethylacetamide and cooled to room temperature, and
52 g of triethylamine was added dropwise via a dropping funnel to
the reaction mixture under stirring. After this addition was
finished, 60 g of 3-bromopropyl methacrylate was added dropwise via
a dropping funnel to the reaction solution under stirring, and the
mixture was reacted for 8 hours.
[0230] After the reaction mixture was cooled to 0.degree. C., 5 M
HCl was added dropwise thereto under stirring until the pH value of
the reaction mixture was reduced to 6 or less. The reaction
solution was poured into 5 L of water to precipitate a polymer.
This product was collected by filtration, washed with water and
dried to give a polymer compound 2.
[0231] By its NMR spectrum, it was confirmed that 30% of the
carboxyl groups of the polymer had been converted into
3-methacryloyloxy propyl ester. The glass transition temperature as
determined by DSC was 110.degree. C., and the weight average
molecular weight as determined by gel permeation chromatography
(GPC) using polystyrene as the standard was 110,000.
Synthesis Example 3
Specific Alkali-Soluble Polymer Compound 3
[0232] 100 g of poly-p-hydroxystyrene having a weight average
molecular weight of 40,000 was dissolved in 500 ml of
N,N-dimethylacetamide in a 1000-ml three-necked flask equipped with
a condenser and a stirrer. 42 g of triethylamine was added dropwise
via a dropping funnel to the solution at room temperature under
stirring. After this addition was finished, 83 g of 3-bromopropyl
methacrylate was added dropwise via a dropping funnel to the
reaction solution under stirring, and the mixture was reacted for 8
hours.
[0233] After the reaction mixture was cooled to 0.degree. C., 5 M
HCl was added dropwise thereto under stirring until the pH value of
the reaction mixture was reduced to 6 or less. The reaction
solution was poured into 5 L of water to precipitate a polymer.
This product was collected by filtration, washed with water and
dried to give a polymer compound 3.
[0234] By its NMR spectrum, it was confirmed that 50% of the
carboxyl groups of the polymer had been converted into
3-methacryloyloxy propyl ether. The glass transition temperature as
determined by DSC was 112.degree. C., and the weight average
molecular weight as determined by gel permeation chromatography
(GPC) using polystyrene as the standard was 50,000.
[0235] The specific alkali-soluble polymer compounds (polymer
compounds 1 to 23) were synthesized in the same manner as in
Synthesis Examples 1 to 3 except that the respective monomers shown
in Tables 1 to 3 were used. Further, Tables 1 to 3 show the
measurement results of the glass transition temperature (Tg in the
tables) of each polymer compound as determined by DSC and the
molecular weight thereof by GPC.
1TABLE 1 No. Compositional ratio (mol-%) Tg(.degree. C.) WAMW* 1 24
105 90000 2 25 110 110000 3 26 112 50000 4 27 108 89000 5 28 110
95000 6 29 110 88000 7 30 114 101000 8 31 112 92000 WAMW*: Weight
average molecular weight
[0236]
2TABLE 2 No. Compositional ratio (mol-%) Tg(.degree. C.) WAMW* 9 32
115 95000 10 33 113 105000 11 34 123 55000 12 35 110 99000 13 36
118 120000 14 37 112 114000 15 38 121 103000 16 39 125 121000
WAMW*: Weight average molecular weight
[0237]
3TABLE 3 No. Compositional ratio (mol-%) Tg(.degree. C.) WAMW* 17
40 116 99000 18 41 118 103000 19 42 120 100000 20 43 108 114000 21
44 110 121000 22 45 114 111000 23 46 110 105000 WAMW*: Weight
average molecular weight
Examples 1 to 4 and Comparative Example 1
[0238] Preparation of a Substrate
[0239] An alloy melt containing 99.5% or more aluminum, 0.30% Fe,
0.10% Si, 0.02% Ti, and 0.013% Cu was subjected to cleaning
treatment and then cast. In this cleaning treatment, the melt was
degassed to remove unnecessary gas such as hydrogen, and filtered
through a ceramic tube filter. Casting was conducted using a DC
casting method. After 10-mm surface layer was removed from the
coagulated ingot plate of 500 mm in thickness, the plate was
subjected to homogenization treatment at 550.degree. C. for 10
hours such that intermetallic compounds were not agglomerated.
Then, the plate was hot-rolled at 400.degree. C., then annealed at
500.degree. C. for 60 seconds in a continuous annealing furnace and
cold-rolled to form an aluminum rolled plate of 0.30 mm in
thickness. By regulating the roughness of pressure rollers, the
central line average surface roughness Ra after cold rolling was
regulated to be 0.2 .mu.m. Thereafter, the plate was placed in a
tension leveler to improve flatness.
[0240] Then, the plate was subjected to surface treatment to form a
substrate for planographic printing plate.
[0241] First, the surface of the aluminum plate was defatted at
50.degree. C. for 30 seconds in 10% aqueous sodium aluminate to
remove the rolling oil therefrom and then neutralized with 30%
aqueous sulfuric acid at 50.degree. C. for 30 seconds, to remove
smuts therefrom.
[0242] Then, the surface of the substrate was roughened (i.e.
grained) thereby facilitating the adhesion of the substrate to a
recording layer while conferring water retention characteristics on
the non-image part. The substrate was subjected to electrolytic
graining by floating the aluminum web in an aqueous solution
containing 1% nitric acid and 0.5% aluminum nitrate at 45.degree.
C. and electrifying it at 240 C/dm.sup.2 at the side of the anode
at a current density of 20 A/dm.sup.2 in an alternating waveform in
the duty ratio of 1:1 from an indirect feeder cell. Thereafter, the
substrate was etched at 50.degree. C. for 30 seconds in 10% aqueous
sodium aluminate and then neutralized with 30% aqueous sulfuric
acid at 50.degree. C. for 30 seconds to remove smuts therefrom.
[0243] Further, the substrate was anodized to form an oxide film
thereon, in order to improve abrasion resistance, chemical
resistance and water retention characteristics. The substrate was
subjected to electrolysis in 20% aqueous sulfuric acid as the
electrolyte at 35.degree. C. at a direct current of 14 A/dm.sup.2
from an indirect feeder cell while floating the aluminum web in the
electrolyte, to form a 2.5 g of/m.sup.2 anodized film thereon.
[0244] Thereafter, the surface of the substrate was rendered
hydrophilic by treating it with a silicate, in order to secure
hydrophilicity on the non-image part in the planographic printing
plate. This treatment was conducted by passing 1.5% aqueous sodium
silicate No. 3 at 70.degree. C. such that the contact time thereof
with the aluminum web was 15 seconds, and then the substrate was
washed with water. The amount of Si adhering thereto was 10
mg/m.sup.2. The Ra (central line surface roughness) of the
substrate thus prepared was 0.25 .mu.m.
[0245] Formation of a Recording Layer
[0246] The recording layer coating solution (P-1) below was
prepared, applied via a wire bar onto the aluminum substrate
obtained in the manner described above, and dried at 115.degree. C.
for 45 seconds in a hot-air oven to form a recording layer to give
a planographic printing plate precursor. The amount of the coating
after drying was in the range of 1.2 to 1.3 g of/m.sup.2.
[0247] The alkali-soluble polymers used in the Examples are the
specific alkali-soluble polymers obtained in the Synthesis Examples
described above, and the structural unit of the alkali-soluble
polymer B-1 used in Comparative Example 1 is shown later. DPHA used
as the radical-polymerizable compound is dipentaerythritol
hexaacrylate.
[0248] Recording Layer Coating Solution (P-1)
[0249] Alkali-soluble polymer: Component (A) (compound shown in
Table 4, in the amount shown in Table 4)
4 Radical-polymerizable compound: Component (D) (compound shown in
Table 4, in the amount shown in Table 4) IR absorber "IR-1":
Component (B) 0.08 g Polymerization initiator "S-1": Component (C)
0.30 g Victoria Pure Blue naphthalene sulfonate 0.04 g
Fluorine-type surfactant 0.01 g (trade name: Megafack F-176, from
Dainippon Ink and Chemicals, Incorporated) p-Methoxyphenol 0.001 g
Methyl ethyl ketone 9.0 g Methanol 10.0 g 1-Methoxy-2-propanol 8.0
g 47 48 49 50
[0250] Evaluation of the Planographic Printing Plate Precursor
[0251] Each of the resultant planographic printing plate precursors
was stored at room temperature for 3 days and then exposed to laser
light, or stored at 60.degree. C. for 3 days without exposure to
laser light, and then measured for the degree of insolubilization
in dimethyl sulfoxide as an index of sensitivity of the recording
layer, in order to evaluate the degree of cure by light exposure
and stability during storage. The light exposure conditions are as
follows. The evaluation results are shown in Table 4 below.
[0252] Light Exposure
[0253] Exposure to light under the conditions of a power of 6.5 W,
an external drum revolution number of 81 rpm, an energy of 188
mJ/cm.sup.2 on the plate and a resolution of 2400 dpi by a
light-exposing machine (trade name: Trendsetter-3244VFS
(manufactured by CREO Co., Ltd.) equipped with a water-cooling 40-W
infrared semiconductor laser.
5 TABLE 4 Content of carbon- Degree of carbon Radical- Degree of
insolubilization Polymeric double polymerizable insolubilization
with with time without compound bonds compound exposure to laser
exposure to light (content) (meq/g) (content) light (%) (%) Example
1 Polymeric 2.1 DPHA 80 0 compound 4 1.0 g 1.0 g Example 2
Polymeric 2.7 DPHA 75 0 compound 3 1.0 g 1.0 g Example 3 Polymeric
2.5 DPHA 77 0 compound 11 1.0 g 1.0 g Example 4 Polymeric 2.4 DPHA
73 0 compound 16 1.0 g 1.0 g Comparative B-1 2.3 DPHA 75 40 Example
1 1.0 g 1.0 g Comparative B-2 1.1 DPHA 25 0 Example 2 1.0 g 1.0
g
[0254] As is evident from Table 4, each planographic printing plate
using the image recording material of the invention was highly
cured by laser light exposure and did not undergo curing with time
during storage in a high-temperature atmosphere, thus achieving a
high degree of cure by light exposure and excellent stability
during storage. On the other hand, the planographic printing plate
in Comparative Example 1, in which the specific alkali-soluble
polymer in the invention was not used, achieved a similar degree of
cure, but the recording layer was cured with time, so there was a
problem with stability during storage.
Examples 5 to 10 and Comparative Examples 2 to 3
[0255] An aluminum substrate similar to that of Example 1 was
coated with a prime-layer coating solution shown below, and dried
for 30 seconds in an atmosphere at 80.degree. C. The amount of the
coating after drying was 10 mg/m.sup.2.
[0256] Prime-Layer Coating Solution
[0257] The following ingredients were mixed to prepare a
prime-layer coating solution.
6 2-Aminoethyl phosphonic acid 0.5 g Methanol 40 g Pure water 60
g
[0258] The recording layer coating solution (P-2) shown below was
prepared, applied via a wire bar onto the undercoating formed on
the substrate, and dried at 115.degree. C. for 45 seconds in a
hot-air oven to give a planographic printing plate precursor. The
amount of the coating after drying was in the range of 1.2 to 1.3 g
of/m.sup.2.
[0259] The alkali-soluble polymers used in the Examples are the
specific alkali-soluble polymers obtained in the Synthesis
Examples, and ATMMT is pentaerythritol tetraacrylate.
[0260] Recording Layer Coating Solution (P-2)
[0261] Alkali-soluble polymer: Component (A) (compound shown in
7 Table 5, in the amount shown in Table 5) Radical-polymerizable
compound: Component (D) (compound shown in Table 5, in the amount
shown in Table 5) IR absorber "IR-2": Component (B) 0.08 g
Polymerization initiator "S-2": Component (C) 0.30 g Victoria Pure
Blue naphthalene sulfonate 0.04 g Fluorine-type surfactant 0.01 g
(trade name: Megafack F-176, from Dainippon Ink and Chemicals,
Incorporated) N-nitro-N-phenyl hydroxyl amine aluminum 0.001 g
Methyl ethyl ketone 9.0 g Methanol 10.0 g 1-Methoxy-2-propanol 8.0
g 51 52 53 Content of carbon-carbon double bond: 1.4 meq/g
[0262] Light Exposure
[0263] The resultant planographic printing plate precursor was
exposed to light under the conditions of a power of 9 W, an
external drum revolution number of 210 rpm, an energy of 133
mJ/cm.sup.2 on the plate and a resolution of 2400 dpi by a
light-exposing machine (trade name: Trendsetter-3244VFS,
manufactured by CREO Co., Ltd.) equipped with a water-cooling 40-W
infrared semiconductor laser.
[0264] Development Treatment
[0265] After light exposure, the planographic printing plate
precursor was subjected to development by an automatic developing
machine (trade name: Stabron900NP, manufactured by Fuji Photo Film
Co., Ltd.). As the developing solution, "D-1" shown below was used
as the charge solution, while "D-2" below was used as the
supplementary solution. The temperature of the development bath was
30.degree. C., and the development time was 12 seconds. The
supplementary solution was automatically introduced so that the
electrical conductance of the developing solution in the automatic
developing machine was kept constant. The finisher used was a
solution of FN-6 (trade name) (Fuji Photo
8 (Developing solution [D-1]) Potassium hydroxide 3 g Potassium
bicarbonate 1 g Potassium carbonate 2 g Sodium sulfite 1 g
Polyethylene glycol mononaphthyl ether 150 g Sodium dibutyl
naphthalene sulfonate 50 g Ethylene diamine tetraacetate
tetrasodium 8 g Water 785 g (Developing solution [D-2]) Potassium
hydroxide 6 g Potassium carbonate 2 g Sodium sulfite 1 g
Polyethylene glycol mononaphthyl ether 150 g Sodium dibutyl
naphthalene sulfonate 50 g Potassium hydroxyethane diphosphonate 4
g Silicon TSA-731 0.1 g (trade name, from GE Toshiba Silicones)
Water 786.9 g
[0266] Evaluation of Printing Resistance
[0267] Then, the planographic printing plate precursor was used in
printing with a printing machine (trade name: Lithron manufactured
by Komori Corporation). How many prints with ink kept at sufficient
concentration could be obtained in printing was determined with
naked eyes, to evaluate printing resistance. The results are
collectively shown in Table 5.
9 TABLE 5 Polymeric Radical- compound polymerizable Printing
(content) compound (content) resistance Example 5 Polymeric none
60,000 prints compound 1 Example 6 Polymeric none 70,000 prints
compound 3 Example 7 Polymeric none 75,000 prints compound 11
Example 8 Polymeric DPHA 65,000 prints compound 4 1.0 g Example 9
Polymeric DPHA 67,000 prints compound 12 1.0 g Example 10 Polymeric
U-1 64,000 prints compound 15 1.0 g Comparative B-1 none 2,000
prints Example 3 2.0 g Comparative B-1 DPHA 10,000 prints Example 4
1.0 g 1.0 g Comparative B-2 DPHA 7,000 prints Example 5 1.0 g 1.0 g
Comparative B-3 DPHA 3,000 prints Example 6 1.0 g 1.0 g
[0268] As can be seen from the results in Table 5, each
planographic printing plate using the image recording material of
the invention as the recording layer has achieved superior printing
resistance to that of Comparative Examples 2 and 3.
Examples 11 to 14 and Comparative Example 4
[0269] Preparation of a Substrate
[0270] After the surface of an aluminum plate of 0.30 mm in
thickness was roughened by graining with a nylon brush and an
aqueous suspension of 400-mesh pumiston (phonetic), and washed
sufficiently with water. The plate was etched by dipping it for 60
seconds in 10 weight-% aqueous sodium hydroxide at 70.degree. C.,
then washed with running water, neutralized and washed with 20
weight-% nitric acid and washed with water. The substrate was
subjected to electrolytic graining with a sine-wave electric
current in an alternating waveform at 12.7 V in 1 weight-% aqueous
nitric acid at 160 C/dm.sup.2 at the side of the anode. The surface
roughness was determined to be 0.6 .mu.m (expressed in Ra).
Thereafter, the substrate was dipped for 2 minutes in 30 weight-%
aqueous sulfuric acid at 55.degree. C. to remove smuts therefrom
and then anodized for 2 minutes at a current density of 2
A/dm.sup.2 in 20 weight-% aqueous sulfuric acid to form a 2.7 g
of/m.sup.2 anodized film. Then, the aluminum plate was coated with
a undercoating solution described later, and then dried in an
atmosphere at 80.degree. C. for 30 seconds. The amount of the
coating after drying was 10 mg/m.sup.2.
[0271] Formation of a Recording Layer
[0272] The recording layer coating solution (P-3) below was
prepared, applied via a wire bar onto the aluminum substrate
obtained in the manner described above, and dried at 115.degree. C.
for 45 seconds in a hot-air oven to form a recording layer thereon,
to give a planographic printing plate precursor. The amount of the
coating after drying was in the range of 1.2 to 1.3 g of/m.sup.2.
The planographic printing plate was subjected to laser scanning
light exposure and development under the same conditions as in
Example 5.
[0273] Recording Layer Coating Solution (P-3)
[0274] Alkali-soluble polymer: Component (A) (compound shown in
Table 6, in the amount shown in Table 6)
10 Radical-polymerizable compound: Component (D) (compound shown in
Table 6, in the amount shown in Table 6) IR absorber "IR-2":
Component (B) 0.08 g Sulfonium salt "S-1": Component (C) 0.30 g
Victoria Pure Blue naphthalene sulfonate 0.04 g Fluorine-type
surfactant 0.01 g (trade name: Megafack F-176, from Dainippon Ink
and Chemicals, Incorporated) t-Butyl catechol 0.001 g Methyl ethyl
ketone 9.0 g Methanol 10.0 g 1-Methoxy-2-propanol 8.0 g 54 55
[0275] The printing plate was used in printing in the same manner
as in Example 5 and evaluated for sensitivity, printing resistance
and staining. Separately, each of the resultant planographic
printing plate precursors was allowed to stand at 60.degree. C. for
3 days, or at 45.degree. C. in 75% relative humidity for 3 days,
and then used in printing in the same manner as above. The results
are collectively shown in Table 6.
11 TABLE 6 Polymeric Radical- Printing resistance/staining in
non-image portion compound polymerizable Not allowed to 45.degree.0
C., 75% (content) compound (content) stand 60.degree. C., 3 days
humidity, 3 days Example 11 Polymeric none 60,000 prints 60,000
prints 60,000 prints compound 1 no stain no stain no stain 2.0 g
Example 12 Polymeric none 55,000 prints 55,000 prints 55,000 prints
compound 11 no stain no stain no stain 2.0 g Example 13 Polymeric
DPHA 0.5 g 65,000 prints 65,000 prints 65,000 prints compound 11
U-1 0.5 g no stain no stain no stain 1.0 g Example 14 Polymeric
DPHA 0.5 g 63,000 prints 63,000 prints 63,000 prints compound 17
U-2 0.5 g no stain no stain no stain 1.0 g Comparative B-1 DPHA 0.5
g 20,000 prints 18,000 prints 10,000 prints Example 7 1.0 g U-1 0.5
g no stain staining staining Comparative B-2 DPHA 0.5 g 15,000
prints 15,000 prints 15,000 prints Example 8 1.0 g U-1 0.5 g no
stain no stain no stain
[0276] As can be seen from Table 6, each planographic printing
plate using the image recording material of the invention as the
recording layer was excellent in printing resistance without
staining on the non-image portion and superior in stability with
time without a reduction in printing resistance or stain resistance
on the non-image portion, even after storage in the
high-temperature and high-humidity environment.
Examples 15 to 18 and Comparative Example 5
[0277] Preparation of a Substrate
[0278] After the surface of an aluminum plate of 0.30 mm in
thickness was roughened by graining with a nylon brush and an
aqueous suspension of 400-mesh pumiston (phonetic), and washed
sufficiently with water. The plate was etched by dipping it for 60
seconds in 10 weight-% aqueous sodium hydroxide at 70.degree. C.,
then washed with running water, neutralized and washed with 20
weight-% nitric acid and washed with water. The substrate was
subjected to electrolytic graining with a sine-wave electric
current in an alternating waveform at 12.7 V in 1 weight-% aqueous
nitric acid at 160 C/dm.sup.2 at the side of the anode. The surface
roughness was determined to be 0.6 .mu.m (expressed in Ra).
Thereafter, the substrate was dipped for 2 minutes in 30 weight-%
aqueous sulfuric acid at 55.degree. C. to remove smuts therefrom
and then anodized for 2 minutes at a current density of 2
A/dm.sup.2 in 20 weight-% aqueous sulfuric acid to form a 2.7 g
of/m.sup.2 anodized film.
[0279] Formation of a Undercoating Layer
[0280] A liquid composition (sol) in the SG method was prepared by
the procedure described below.
12 Sol composition Methanol 130 g Water 20 g 85 weight - %
phosphoric acid 16 g Tetraethoxysilane 50 g 3-Methacryloxypropyl
trimethoxysilane 60 g
[0281] The above components for the sol composition were mixed and
stirred. About 5 minutes later, exothermic reaction was recognized.
The mixture was reacted for 60 minutes and then transferred to
another vessel, and 3000 g of methanol was added to it, to give
sol.
[0282] This sol was diluted with methanol/ethylene glycol (9/1 by
weight) and applied onto the substrate to give a coating containing
Si in an amount of 30 mg/m.sup.2 thereon, and the coating was dried
at 100.degree. C. for 1 minute.
[0283] The recording layer coating solution (P-4) having the
composition shown below was applied via a wire bar onto the prime
coating on the aluminum substrate thus treated, and dried at
115.degree. C. for 45 seconds in a hot-air oven to prepare a
planographic printing plate precursor. The amount of the coating
after drying was in the range of 1.2 to 1.3 g of/m.sup.2.
[0284] Recording Layer Coating Solution (P-4)
[0285] Alkali-soluble polymer: Component (A) (compound shown in
Table 7, in the amount shown in Table 7)
[0286] Radical-polymerizable compound: Component (D) (compound
shown in Table 7, in the amount shown in Table 7)
13 IR absorber "IR-1": Component (B) 0.08 g Sulfonium salt "S-1":
Component (C) 0.30 g Victoria Pure Blue naphthalene sulfonate 0.04
g Fluorine-type surfactant 0.01 g (trade name: Megafack F-176, from
Dainippon Ink and Chemicals, Incorporated) Methyl ethyl ketone 9.0
g Methanol 10.0 g p-Methoxy phenol 0.001 g 1-Methoxy-2-propanol 8.0
g
[0287] Light Exposure
[0288] The resultant planographic printing plate was exposed to
light under the conditions of a power of 250 mW per beam, an
external drum revolution number of 800 rpm and a resolution of 2400
dpi by a light-exposing machine (trade name: Luxel T-9000CTP
manufactured by Fuji Photo Film Co., Ltd.) equipped with a
multi-channel head.
[0289] Development Treatment
[0290] After light exposure, the planographic printing plate
precursor was subjected to development by an automatic developing
machine (trade name: Stabron 900N, manufactured by Fuji Photo Film
Co., Ltd.). As the developing solution, both the charge solution
and its supplementary solution were solutions of DP-4 (trade name)
(Fuji Photo Film Co., Ltd.) diluted with water in a ratio of 1:8.
The temperature of the development bath was 30.degree. C. The
finisher used was a solution of GU-7 (trade name) (Fuji Photo Film
Co., Ltd.) diluted with water in a ratio of 1:2.
[0291] Evaluation of Printing Resistance and Staining
[0292] Then, the planographic printing plate was used in printing
with a printing machine (trade name: SOR-KZ manufactured by
Heidelberg) How many prints with ink kept at sufficient
concentration could be obtained in printing was determined to
evaluate printing resistance. The resultant prints were evaluated
with naked eyes for staining on the non-image portion. The results
are collectively shown in Table 7.
14 TABLE 7 Radical- Polymeric polymerizable Staining on compound
compound Printing non-image (content) (content) resistance portion
Example 15 Polymeric none 80,000 no stain compound 2 prints 2.0 g
Example 16 Polymeric DPHA 82,000 no stain compound 2 1.0 g prints
1.0 g Example 17 Polymeric DPHA 85,000 no stain compound 19 1.0 g
prints 2.0 g Example 18 Polymeric DPHA 81,000 no stain compound 5
1.0 g prints 1.0 g Comparative B-1 DPHA 20,000 staining Example 5
1.0 g 1.0 g prints
[0293] As can be seen from Table 7, each planographic printing
plate using the image recording material of the invention as the
recording layer was excellent in printing resistance without
staining on the non-image portion.
[0294] The image recording material of the invention comprises an
alkali-soluble polymer with specific Tg having an unsaturated group
in a side chain thereof and is thus excellent in stability during
storage and superior in image formability with high-strength image
portions. Further, when the image forming material of the invention
is used as a recording layer for a planographic printing plate
precursor, the planographic printing plate precursor is excellent
in stability during storage and can be used in printing with an
infrared laser to achieve excellent printing resistance.
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